You can also cut down a 4 or 5 bank to make a 3 bank if you have no luck with finding some 3 banks. Probably easier & cheaper too to find 4 & 5 banks I guess as they don't have the same demand.
The bank on the left in the pic is an original 3 bank, the bank on the right is a 5 bank (from Flash) cut down to a 3 bank. The result is the same. One of the mounting arms/strap is cut off when the plate is cut down, but the strap has to be cut off anyway on a 3 bank to make it fit. They are not needed.
Quoted from ejacques:Those horseshoe contacts might as well be made from 24k gold if you can find them.
Flippers.com have new horseshoe contacts for $10.00 each, but no need. You can clean up used ones & the key to reliability is to place another horsehoe with the contacts removed behind it to essentially double the tension.
Once the contact pairs were cleaned up & the tension adjusted they worked flawlessly for more a year or so now for me.
Here is a pic of what I mean to get the idea (I only have a pic of the dirty contact before I cleaned it).
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