A few months back I had a tire give up the ghost on me. I pulled the never used compact from the trunk and couldn't fit the flat 18" in the trunk, so a full-size spare is out of the question. The next morning pulled out of the garage and some kids waiting for the school bus on my street told me the spare was flat. I found a pair of good used tires (turned out to be runflats) and had them mounted. Last week I apparently picked up some screws from the street next to a new townhouse development downtown and developed a slow leak... a slow leak that's difficult if not impossible to detect in runflats without TPMS. Long story short I destroyed the runflat.. it was trashed but it got me home.
So I need a new compact spare, size 125/70 R18, but have not a clue wher to find one. Checked the usual suspects, couldn't find anything on Tire. Rack or Discount, et al. The Google machine wasn't much of a help, just lots of links to for sale ads on forums, but I seriously don't want to buy a used one as the ten year old brand new one in the TT didn't make it 20 miles or 24 hours bolted to the car. And as stated previously, a full size rim and tire won't fit in the roadster.
Also, don't use runflats without TPMS, and don't use runflats on rims that weren't designed for them. The tire guy had one hell of a time removing the shredded tire and as nearly a difficult time removing the good one. (We didn't know they were runflats until they were removed)