What  I do when I need these things is as Mr Happy is saying, sort of, I make my own and drop them into Session Drummers folder.
I have recorded my real Drums and egg shakers, even a railroad spike, 
Session drummer can play wave files. I top and tale the sample in Wave Lab. 
Then you add them to the little octapad in Session drummer and have 100% control over placement.  
I find searching for just the right sample tediously painful so this works for me. 

I tried it: Loop construction tool is the way to go!
It seems to be faster to record & create the loop than search it from all the gigabytes around the disk.
 
 

panup
I tried it: Loop construction tool is the way to go!
It seems to be faster to record & create the loop than search it from all the gigabytes around the disk.
 
 

Exactly my experience too. 
I'll have to try the loop tool, didn't even know it existed. Good one Mr Happy. 

If you use shakers/tambourines regularly, you might be interested in at least looking at Shimmer Shake Strike by In Session Audio. It's a library, so works with Kontakt Player. Full Kontakt not required. They are currently selling it with the expansion for the price of the VI itself ($100; this was also the launch special, the price I paid; they don't do $29 deals). It's not cheap, but there's nothing more realistic. It even adjusts or eliminates the prebeat part of the shake for high BPM songs.
 
https://insessionaudio.com/products/shimmer-shake-strike/
 

I checked Shimmer Shake Strike demos. High quality stuff, a little overkill for my purpose but it could be useful in my future productions.
 
There is Valentine Sale "Shimmer Shake Strike with Expansion  × 1: $99" ($40 off).
Where's my credit card...
 

I purchased Shimmer Shake Strike. Learning curve was steep but short and in 5 minutes I had created the first shaker + tambourine track. Good stuff!

∞

I also created my own shaker and tambourine loops in the Loop Construction window. It is very straightforward to use and it took under 10 minutes to create a loop, editing, processing and saving it to disk.
 
I noticed lots of things to improvce in the loop constuction tool. Hey Bakers, could you please return to Cakewalk HQ for a minute and fulfil my wishes?

∞