Good question..I purchased them from a previous Porsche owner who had them on his '08 C2 S. They are 18's not 19's. I can measure the width of the tire if you need to know.

 

Thought I'd revive this thread with another alleggerita 18" setup. 235/40/18 and 265/40/18 Pirelli winter 240 sottozero serie ii on 18x8, 18x10. I added 5mm spacers on the rear to take it 3mm out further than stock.

 

There is a very good firm in Calif. that offers original equipment wheels. The 18" Carrera IV's I got last year were new (substituted for an upgrade on a '09 911). I had TireRack ship the winter PA2 Michelin's direct to Wheel Enhancement and the mounted tires came direct to me; $550 ea. w/ TPM and mounting; 11" wide w/ 295 profile for the rears. I did the install in 30 mins. (w/ a good lift/jack).
Of noted : the manuf. of these OEM wheels was BBS. I'm not certain how much Victors run but the Porsche wheels IMO look great.