Inflatable spare alternative?
 

I'm looking for a real spare tire/wheel to take with me to the track, so in case of a flat I can still run the remaining sessions. I'm sure the stock one would be frowned on.
I'll be looking at wrecking yards first, anyone know if there are other cars that are interchangeable? Just a steel wheel or whatever.

I've got a few sets of Cookie Cutters. Look around for a bit and you'll find them pretty cheap.

I wouldn't run on the track on mis-matched tires. Your best bet, since you're Spec bound, is to get another full set of track wheels.

Unless your roll cage has a long diagonal tube through the rear hatch area, it's pretty easy to get a full set of wheels/tires back there. Once the passenger seat is out, there's lots of room for your jack, tools, cooler full of snacks, racing gear, yada yada.....

For 944 spec, I think wheels are limited to 7" max width. 7x15 Cookies are perfect for your early offset 944. You can find them for about $200/set.

As usual, I was unclear...
I'm just doing HPDE instruction sessions right now on regular street tires. Just need something to put a matching tire on if I get a flat. People don't generally want to sell just 1 porsche wheel, so I didn't know if there's something else compatible for temp use.
When I move up to Spec, I'll be transporting it on a trailer with the whole setup.

Okay, makes sense.

-Wrecking yards
-Swap meets
-Used parts section here at Pelican.
-Buy a set of Cookie Cutters, and mount just one tire.

Keep your antennas up, and something will pop up before long.