Yeah, that's a blank door that was customized. I don't recognize the parts that remain, so who knows.
For early WPC games, they used Coin Controls doors.
Typically, I've seen the 3-slot variant like this, but with the appropriate coinage labels:
The US door was the same, but just had 2 coin slots, rather than 3:
I've seen this style of coin door on a couple WPC games, though I'm not entirely certain that it's era appropriate. It's also a Coin Controls door, but it seems like it might actually be for Data East games that were possibly converted for use for WPC games by swapping the coin door's harness.
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