Wanted - Needed, gas cap for 80 XS400 HS

[Old Mose]

I'm rebuilding my bike after a serious wreck. Different frame required a different gas tank which didn't come with a cap. I had two caps from different years but even though they look alike the geometry is wrong. Does anyone have a cap that will work?

 

[NA3S]

I have a nice one with matching key and mounting screw... It's originally off of a '78 XS650, but is the same part # as the '80 XS400 - http://www.partzilla.com/parts/detail/yamaha/YP-4R0-24602-01-00.html

PM me if you're interested.