I'm preferring the look of these P90s over the full metal cased Humbuckers. They are Nickel case with a black bobbin. I removed the black plastic pickguard ages ago in favour of seeing more grain and colour. Now I've added more black in and I'm not quite settled. So these are in the back of my mind for next year when in the UK
 
 
 
For a long time, I wonderd why the chrome reacted to the Vietnamese climate differently than the chrome on my other guitars. Than I found maybe mine was nickle. These new pickups are nickel, but don't quite match. they have a darkness to their colour. Maybe that will in time

Chrome is shinier than nickel, and looks blue while nickel has a hint of yellow.

Nickel turns yellow as it wears/corrodes/ages, polishing usually gets it back to where it should be. I prefer the look of nickel but understand why manufacturers use chrome - it’s tougher and resists corrosion much more than nickel does.

These new pickups are nether looking blue or yellow. But I think the yellow will come with the Vietnamese weather. I preferred the nickel when I could get it shinier, but it changes way too quick here. 
 
Silver gets really hammered here, I can't leave my flutes out. I've noticed some jewelers put a grlic in each dispplay case. I can't find anything to verify the validity of this. 
 
My Brand new Guild had been in Vietnam a month and the b and e strings already look old. String corrsion in Vietnam drives my Australian friend mad, with his collection.

If a surface is perfectly polished with no barrier to oxygen/moisture, it will oxidize in short order. A polish that leaves a residue, like Mothers Mag & Aluminum Polish (used on car wheels), would protect better and can you could do a quick buff every now and then. If you have an auto store that carries such, it is worth grabbing some. That stuff is designed to protect from brake dust, which is one of the more corrosive agents there is to metal, especially bare aluminum.

Glad you were able to repair the pick up.  Excellent troubleshooting.
 
Pickups modeled to represent vintage pick ups  typically use an iron alloy, alnico (iron, aluminium, nickel and cobalt) for their bar material.  You may this page on pick up repair parts interesting:  https://www.stewmac.com/Pickups_and_Electronics/Pickup_Kits_and_Parts/  Stewart McDonald (StewMac) ships world wide.
 
I ran across these pictures of a Vietnam guitar factory that you may enjoy:  https://www.harmonycentral.com/forum/forum/guitar/acapella-42/1313036-
 
I found a guitar factory while working in Taiwan in the seventies.  The factory bread and butter item was a Strat inspired electric guitars sold by JC Penny during Christmas season for $99 US.  The owner spent six months out of the year traveling the world selecting and purchasing small lots of wood used to make his self designed acoustic and electric guitars.  He built me an electric bass modeled on a Fender jazz bass, an acoustic 12 string and an acoustic 6 string.  I no longer have the bass and 6 string but still have the 12 string and play it almost every day.
 
I also found an article about a street in Ho Chi Minh City nicknamed "Guitar Street" because more than 15 manufacturers located on that single street.  https://guitarchitecture.org/2010/07/19/guitar-street-in-ho-chi-minh-city-vietnam/  I figured you might like to visit.

Cool pics I some interesting twoods in their. I seen one of these in a shop window.

 
A few years back a friend wanted a guitar, when she was traveling through., I was living in HCMC city at the time, so we hunted out guitar street. I was as clued up about gutars as I am now (Not that I know much now, but I knew nothing then)
 
Some friends who are experience players up here, say you can pick up decent guitars here, that are worth picking over the lower end Taylors for the cost.
 
They love acoustics here, and you see guitars bags on peoples backs often as the ride their scooters around town. Acoustic basses still having really taken off, there is this city for sale (Fender T-Bucket) and you can see from the strings it's been their a while. Previously there was a Takemine, with a truss rod so tight you couldn't play it, and they wouldn't let you adjust or be bothered to do it themsleves. Fortunatly the gamble paid off, and it sits in my place with Nylon Tapewounds on it, sounds very nice. 

So it seesm there are two types or nickel finish. Normal Nickel and Black Nickel. Black Nickel if a plating treatment that can create varying amounts of black tone to the nickel, and is more corrosion resistant and still conductive.
 
So seems my new nickel pickups will never quite match my nickel hardware