Anyone know where I can get a Wadia 861 board?

It is worth taking to a local repair shop. It looks like the outputs are discrete amplifier sections. If your problem is there, it will allow a qualified repair person to quickly diagnose and replace bad parts and chances are good for finding the right part.

I would be happy to sell you my 861SE with GNSC Statemet mods which has a finicky laser which I end up using mostly for the DAC section .  It has a much better transport and the kids are great.  I bet Wadia can swap lasers and you would end up with a better machine.  Feel free to contact me at convergent1@comcast.net

Andrew

Did you try George Meyer AV?

If you were in Australia I'd have a look as I've been inside these a bit doing mods.
Cheers George

George Meyer was useless, no 861 parts
As for Australia; I can send you the board if you think you can repair the right channel output module? 
Please pm details if interested.