Hi Jens, 15x8's aren't that hard to find here. Summit can also often get what it doesn't show. Bias ply rayon or nylon with a thin racing stripe were what originally came on your Vette. The bias ply tires drive better with the OEM suspension settings tune. But, with some suspension upgrades and different settings, belted radials can be used to greatly improve traction and handling. I buy a lot of radial Cooper tires reasonably through Summit using their "Best Price Guarantee". The '81 GMC sits on a set of Discoverer A/T3, 235 /75R15, Radial, T Speed Rating, 104 Load Range, Open White Letters on 7" rims - and rides, and handles good. My '85 TA sits on Cooper Zeon Radial 245x50 ZR16 on 8" rims - the TA handles the road like it is glued there - but it also has all of the UMI performance suspension upgrades they make. Your factory rims would have been 7x15, and a good tire would be the Cooper Cobra GT, P225/70R15, Radial, 1,753 lbs. Maximum Load, T Speed Rating, Solid White Letters with 7" wide rims. For 8x15 rims, you'll need to pay more attention to wheel offset, but Cobra GT, P255/60R15, Radial, 1,885 lbs. Maximum Load, T Speed Rating, Solid White Letters might be what you want - with the proper suspension settings for radials. I used to run Goodyear P255/60 HR15 on a '79 Vette with 8x15 rims. The '79 had zero interference problems and handled fairly well for a Vette with close ratio steering running the Goodyears. The Goodyears just weren't tires that wore well over time. About 20,000 miles was the life of them before a new set was needed. I can't be sure these tires won't scrub but, if your '71 Vette has the same wheel wells and rim offset my OEM '79 had, this size will work perfectly.