Nearly every 15" street tire out there is marketed as a cosmetic performance tire. IE, they look really good on a classic, have an S or T speed rating for casual driving, and tread depth that will outlast their sidewall life because of their 400+ treadwear rating. However, most of these are under $200 for even the widest sizes.

There also are a host of racing tires in 15" due to many sanctioning body's requirements to stick with 15" diameters as a cost saving measure, despite being $200+ per tire. Some of these have d.o.t. approval as a means to met certain rules requirements but they aren't necessarily street tires because of significantly reduced tread depth and ultra soft compounds. However, if you don't mind paying twice as much for a tire who's tread life is a better match to actual usage and proves really good grip (200 tw rating or less), then some of these may work.

There isn't a lot of middle ground any more. Maxxis and Mickey Thompson are the only two that could fall into this category these days with their carcass design and speed ratings but the Maxxis has a pretty high tread wear rating, so it isn't the stickiest thing out there. MT does not provide tread wear ratings, but claims 15-20k is possible with their SR series, so it obviously is on the softer side. BTW, neither of these is available with a raised white letter sidewall either, a primary consideration for a large number of tire buyers in these forums.