Thanks EightBySix !
not bad, I found 2 there:
75235__creek23__cha_ching.wav
29643__tweeterdj__Coin_into_Slot.wav (I think I like this one better)
still looking, something that comes to mind is the coin drop, 45 record mount at the beginning of "Rock Around the Clock" (I think that's the song I'm thinking of.
I'm going to see if I can edit it out of there.
but still looking for suggestions.