Summer only tires are in the 100-300 UTOQ Range. All Season 40k Mile Tires UTOQ 400-500 Range, 60k Mile Tires I saw some out there with 7-800 UTOQ Ratings. We are driving very light cars, the lower the UTOQ Rating theoretically the stickier the tires will be. Again other factors play into the sticky / tread wear / handling capability. I found the Tire Easy Web Site pretty easy to use and they have every Asian Brand of 13" Tires on their site that you have never heard of before. Bugeyes can handle wider tires than a SWA which pretty much is limited to a 155/80/13 Profile anything more usually will rub. The Tire Easy Site also has information on Minimum / Maximum Rim Width based on Tire Size.
Tire Rack has Discontinued General Altimax RT's under $40 a tire on a CloseOut. I've seen comment from some folks that have used this tire on a BE 175/70/13. Too big to fit a SWA Spridget. With all of the Asian Brands on the Tire Easy Site YMMV. But there are a variety of choices available at the Tire Easy Site. Quality however and suitability for a Spridget, well YMMV.
Keep in mind likely you will not be able to wear any of these out in normal driving. They will age out > 8 years, before you will wear them out in normal driving. And again a 1500 lb car puts far less wear and tear on tread life than a 3,000 lb + car. Good luck in tire hunting.