There were a plethora of makers for tools.
If you look through the parts catalogue or the list in TM9-803 you will also see the tools listed with their drawing number (e.g. 41-W-xxxx) Manufacturers are not listed and as such any tool maching that drawing number might be fair game.
the fact that the kit in the tools section of the website includes a set of Fairmont wrenches supports the claim that these were issued with MB's.
The Photo of the Barcalo wrenches associated with GPW specific items in ORD-7 supports their use in GPW kits.
This does not mean that other makers were not used, nor does it indicate that a GPW could not have been equiped with Fairmont wrenches and that an MB could not have been issued with Barcalow wrenches.
Also it would not be atypical to see a vehicle in service with the odd tool made by a different maker. A defective, lost, or broken tool could have been replaced with anything.
To my mind one of the "holy grails" of tool kits is a complete set of wrenches made by the same manufacturer. I have nearly completed my fairmont set and also my Barcalo set. Each needs only one wrench to be complete.
As it is I can put together a complete set of mismatched (by maker) wrenches.
Jeep myopia aside, I have also found lots of cool GI tools at garage and estate sales, flee markets and junk shops. Things like trouble lights, inspection lights, jacks, canvas items boxes of several types, paint, cotters, wrenches, flux, multi meters, etc. What can I say,..I love tools,..especially GI ones
In fact I was at an estate sale recently and heard a woman complaining about how her husband was always buying worn out rusty junk tools at estate sales. That by the time they would get in the sale all the dealers and other "men" had purchased all the good tools. What she failed to realize was that often times those junk tools include that rare and sought after blivet we need for our tool kits, spare parts kits or collections.
I also look for packing materials, Yesterday I found an entire roll of foil backed craft paper of the kind used for the accesory packs for 5 in 1 and 10 in 1 rations, and the wound (sulfadiazine) tablets, I also recently purchased a roll of string reinforced olive drab wrapping paper at another sale.
Well I better end this monotribe and get some sleep.
Thanks for letting me vent guys.