I would try online auction sites, flea markets, train shows, swap meets....
Any manufacturer is fair game and searching for an unpowered dummy increases your odds. You could even find a powered one with a bad engine, remove the drive train and there you go. Your prototype railroad (BNSF) could even run BN or SF locomotives. Lots of options out there.

That's a big help, seeing the diagram. Appreciate you sending it!

Thanks! That's just the info I was looking for.

I have a new Bachmann DD40AX "DCC on board" on its way, and wondering if I can put it on my DC layout immediately or if it requires making an adjustment to the decoder?
It is advertised as dual mode, but not being DCC-savvy not sure what is entailed.
Thanks