Carter AVS Gasket / Spacer help!

I need some help with a stock set up. I have a Carter AVS that I want to mount to a stock 340 cast iron intake. The problem I have is where do I find the gasket / spacer. It appears in order to make the factory choke work, the carb needs a spacer. Correct me if I'm wrong. Any help would be greatly appreciated. Thanks. Dave
Part number for a McCord gasket is 39997(66-0198), Holley number is 108-12...these are about 5/16" thick. Steve

Don't know how smiley got in there, doesn't show up when I edit! Should be 66-0198....