Mesh
If it is just tubes to be replaced.
I would write all the tube numbers down, then google them and find out who has the best price on them and order and replace.....
If you cannot find the tube numbers then get out the manual.....if you have lost your manual then go to the Mesa website and look for it in PDF format....or google that .....trust me you should be able to find it some where inside of 15 or 20 minutes......the manual should state what the numbers or kind of tubes are in that thing....if not......Google (is your friend) then and you should be able to find this information out......I do it all the time......and tubes are not really that expensive.....unless you really go for the absoulte high end!!!!!!
Now if it is electronics ummm that would be out of my league...
But if it is dirty pots then go to radio shack and get some spray cleaner and clean them up...
Maybe take a vacum cleaner (and VERY Carefully) vacum out all the dust bunnies and such....
Many times it is only a couple of screws and the electronic base will come out of the amp....a dry paint brush will brush all the dust out....run the vacum while you do this...the pots on the front panel may just need some spray cleaner....the tubes just pull out and push in......After you clean ....
Maybe look for some broken wires or poor soldered joints and all it may need is to be resoldered.....
A lot of times it is some very simple repairs you can do yourself......if it does get too complicated you can ALWAYS go to the tech to have what you do not know or understand fix for you.....but you could be money ahead by just looking and trying yourself....
Just saying brother....but at least try...
Cclifford