Having trouble finding the right combination wheel/tire to be used as a show spare for my 68 convertible. Any suggestions?

Are you just looking for the standard wheel/tire that came with the car? these were 14" wheels.

my spare (if and when I trow it in the car which is never) is a std rim and a thin tyre of the same diameter as the wide tyres on the car....
Takes up less room on a trip in the trunk.
Also having diff diameter wheels on the rear causes problems if u have a posi diff...and not a good idea for a std diff either.

I went to the salavage yard and got a space saver tire and rim for $15. It came off a late 80's S-10 blazer