50 years ago many cars besides the Pantera had folding-sidewall spares. Today, many cars don't come with any kind of spare tire. BFG and G'year stopped making folding sidewall tires 25 yrs ago. I spent weeks trying to find one and tire shop personnel didn't even know what I was talking about when I brought one in. I'm told that Vredelstein in Europe still makes some sizes but I was unable to contact them from the US. Any used ones you might find are 20-40 years old so use one at your own responsibility.You occasionally see display examples on E-Bay.
The next generation spare was the motorcycle-sized high pressure spare. I took a junkyard example from a mid '80s Thunderbird coupe, TIG-welded 2 of the 4 lug nut holes closed in the forged wheel, redrilled it to fit a Ford/Pantera hub and it fit with some rearranging in both trunks as well as on both ends of the Pantera. Now even those are less than safe to use. If you actually want to use one I have no solution except a cell phone and a credit card. Sorry-