Are there any retailers other than Horizon, Tower, Chief, and B&B that sell G-45 parts?

Have you tried Dave's Discount Motors? They use to have parts for the larger Zenoah stuff. They will probably call it a 450.

Dave’s still has them and listed under aircraft engines

What parts are you looking for?
WT

Never heard of Dave’s so thanks for that. I need the insulator block, insulator block gasket, carb mounting screws, and insulator block mounting screws.

Even though Horizon doesn’t show it, if you call someone in sales they have the isolator block that turns the carb so that the throttle arm is straight in line with your throttle rod. I ordered a couple for the G-62’s we flew at Joe Nall as well as one for the G-45.
WT
Just did a check: the G-45 part no. ZEN14510 is discontinued....
I must have gotten one of their last parts.