Fuel tank-Petcock gasket

[Rude]

I have a 1964 356c, with a gas tank from a 1963sc. The gasket on the petcock valve started leaking. I am having trouble finding a replacement gasket. Any suggestions??
I am new here, and tried to locate the gasket in the online parts catalog, with no luck. Found a lot of other items though.
If anyone can be of help, I would appreciate it.

[C. Clark]

*************, http://store.partsobsolete.com/356shopcom.html
Chas.
356
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