AMT did a 1/25 '67 Z28 that, if not currently in production, isn't rare at all and should be fairly cheap. It's a fairly decent kit, especially if you apply the little tweaks I describe in a tutorial in the Tips section here.
There's also a metal-body '68 Z kit (I think by Testor) that's pretty nice. Oh, AMT did '68 Z, too, which is on the shelves now, but you mentioned a preference for '67.
If you must have a more detailed chassis/engine, you can use those units from Revell's '69 Z. Be advised that the Revell dual-quad induction will not fit under the flat (non-CI) hood--not with the air cleaner on, anyway.
ETA: Out of curiosity, I just google-fu'ed the particular Jodiemobile you reference. It's a '68, not a '67, and has Style Trim Group (though not RS), rear spoiler (optional, not standard in '68), and a '69 Cowl Induction hood (available in the Revell '69 kit). Seems to be riding on Chevy Rally Wheels (possibly 15x7--they look pretty good size) with '67 center caps. That's about all I could tell from the 2-3 seconds I got on you2be.