I also couldn't find them and I only need 1 
Yeah I need 4 for my Galaxian coin mech. But I might need more once I'll convert my MB to DK.
I am very glad I still got the Asahi Seiko parts when Nerdtendo had them available. He's almost completely out of stuff now. Only solution is to buy complete mechs at mikesarcade for a whopping 65 USD....but those are the "DK" mechs with the flat faceplates.
Asahi Seiko stopped production of coin-mechs, not a big surprise since everything "coin" operated switches to swipe cards etc.
However, you can answer my question Gyruss......are they the same ?

(In diameter, you can compare the "heads" you can see)