Where could I buy the metal stops/spacers that that are at the end of a buzz bait (between the bent end of the buzz bait arm and the blade)? I am specifically trying to find the stops/spacers in a larger size than are currently on standard buzz baits. Do they come in different sizes?

Some tackle shops carry them but you can order them from lots of online sites. I get a lot of my lure building supplies from an online site but I don't know if they make different sized spacers for buzzbaits like you're looking for.

Check out Lure Parts Online, Jann's Netcraft or Barlow's. All online lure parts places, just do a search for them.

you could also look at a hardware store. Its a pop rivit. Most of them have the pin down the middle though.

They do come in different sizes. In addition to the other websites the others gave you, try staminainc.com. They have good prices and everything you're looking for.

John may have them at Ztackle.