Inert, expensive, BOTIQUE!
Let's corner the market and then sell it to the Porsche
I assume you're talking about the "space saver" spare and it's original can that's missing now? I've used all three suggestions so far and will tell you NOT to use fix-a-flat!!! It's got this stuff in it that eats away the paint on the rim and will corrode the metal underneath if left in the tire/rim. Don't let the parts store sell you fix-a-flat for the canned air mentioned above!
Nice thing about the battery operated compressor: you can do ALL your tires with it, and that cute girlies tires, too. Broken down out in the middle of nowhere...
I just so happen to have an extra and it's brand new. Yep, that's right. It's never been inflated, still has the factory ink stamping on the tire. The rim is perfect and is black in color... I thought they all were... I also have the screw down thing that holds the tire in the compartment. Picked it up out of a 77 280Z.
Make me an offer and we can "Wheel and Deal"...
BTW, I'm in the San Francisco Bay Area... and I would guess that this thing weighs a good 25 lbs. So shipping will cost a few dollars.