Rims for 944

I have a 1984 porsche 944 and I want some black rims. They are very hard to find so I am looking at putting an adapter on my bolt pattern so i could put normal 5 lug rims on it. That way i can pick more my kind of rim too. Has anyone tried the adapters? They seem like a good idea to me. here is the link for one typehttp://cgi.ebay.com/ebaymotors/SET-4-5x112-5X130-5x4-5-WHEEL-ADAPTERS-_W0QQcmdZViewItemQQhashZitem2c5427ffb1QQitemZ19039 0468529QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccesso ries#ht_1007wt_982

if i did that then the next question is how big of a rim can i put on? I want a 16 or 17 in rim. I found some nice 17in rims but what size tire would I want? Would 215/50/17 work good? let me know what the best size would be and would fit good for both a 16in rim and a 17in rim.

Thanks,
Nate