Try this thread for used parts.
http://board.marlincrawler.com/index.php?topic=39620.msg1042965;topicseen#new Or post up in the "Wanted" section. Hit up Tgmaul88 on here, I've gotten some really good deals from him.
I agree Nate, they are picky little bastards. It took me over 6 years to finally get mine dialed in. And I still had to mess with the choke set point in the spring and fall. Once in a a while, my idle screw would back out. But locktite took care of that. I miss the power that it had. Way more than my 22RE has! And it loved long steep climbs on the road. When I would go over the pass, I'd down shift, and give it gas, and it would slowly start to climb rpm's, and keep going till I had to back out of the throttle. That's what I miss about carbs vs. EFI. Give it skinny, and let it go!!
