[racer]

Does your 914 have alloys already or did it come with Steel wheels?

Years ago, I cracked several steel wheels using a 1990s performance tire.. A modern performance tire will put significant cornering loads into a suspension designed to run a 165/80 tire.

That said, you don't need "a lot" of choices.. you only need 1 that works for you. A 205/50 performance tire is commonly available (thank you Mazda for the many Miatas you built that run 15" rims and are still around today)... my 914/6 runs 14" rims.. there's almost no selection for that in a performance tire.. but the 1 that is (Falkin Azenis RT615), is pretty darn good.

I would focus more on getting mechanicals straightened out on a 50 year old car (as needed/if needed) than worry about the bling of 17" aftermarket wheels.