ferraripartsexchange.com has some last I checked. Otherwise you can always watch eBay or if you really want to take it in the shorts call up your local F-car dealership.
Arie I have a set of 360 wheels with brand new tires for sale. they will bolt right up to your 348 and look awesome. give me a ring. 203 847 3757 ex11 cya pETE