Quoted from PinMonk:MEI/Mars 110/120v bill acceptor with a 300 bill stacker. $1 ones that aren't reprogrammable are cheap ($100-$125 used) and fine, but if you spring for the ones that are reprogrammable and can take $1,$5,$10,$20 you can make $5 an option and you'll be surprised how many $5s you'll find in the mix when you collect. 12v acceptors are the most expensive because you rarely see them used for cheap.
Which acceptors are reprogrammable to take $1, $5, $10, $20? Where can I buy those from to put on my new stern pins? link? Thanks!