Not a whole lot, last I checked. There are also a number of different versions out there (Falcon, Orca, Scramble bootleg, Galaxian bootleg, etc.) and prices will likely depend on which versions you have.
If it were me, I'd say $50 confirmed working as a starting number. They are basically fairly common grey market / bootleg games so probably won't command much pricewise, but given the uptick in interest in Donkey Kong over the last few years that may have changed.
Late edit: from what I can tell, it looks as though all of the PCBs you have are Falcon boards. They're probably the most common version out there, and will probably come up as 'Crazy Kong Part II' when powered-up. However, there are a couple of different sets out there so given the number of boards that you have you'd probably want to dump them and compare against what's already-known to figure out what is and isn't there.