nice pic.

might have to do a little better than that.
my best guess is the system is probably made by the company who made the game/machine.
where you just looking to just accumulate the money? or are you looking to rebuild the unit?
if it's the first, there is an easy solution i have used from
http://arbortronics.com/ just ring them up and tell them you need an accumulator board to take 2 coins to pulse one credit. (or 3 or 4 or however many you want) I've purchased a few units from them. they'll roll you up a small credit board. just wire it in line and it's good to go.
if you are looking to rebuild, you might be out of luck....you might end up having to manually hand make parts. The company and it's replacement parts are probably long gone.
without knowing what your plans are, or what you have there, I'm not able to suggest too much.