Hi. It is a great hobby. It is one of mine too. Nothing like buying an old antique missing a part or two, then restoring it to full function. Get a C&R license. Very little downside other than the record keeping and if you aren't in NY, NJ or someplace like that it lets you cross a state border while shopping for 50+ year old acquisitions. Print up some business cards, your name, broken guns wanted, and your phone # and email address.
pawn shops, keep trying, give them your card and tell them you are looking for busted guns.
local gun stores and smiths, ibid.
gun shows. Spread around your cards and keep a few copies of your FFL in your pocket when you go with some cash.
You should start finding them fairly quickly.
Bottom of the barrel, check out Numrich, Sarco and Century Arms, sometimes they have stuff no one else wants.