This may not be of much help since I live in Pennsylvania, but there's a convention here called Steel City Con that's held multiple times throughout the year, and 90% of the convention is a huuuuuuuge vendor hall of people selling older toys, newer toys, other merch, etc. I've bought several old G1s and G3s, and even G4s, from people at that con. Seriously...countless tables of awesome toys! Maybe see if there's a convention/fair of some sort like that around you?
Good luck!