I too have a curbed driveway and don't have any problems when enter / leaving at an angle.
As far as finding a Boxster goes, I would suggest talking to Davis Speight at Boardwalk Porsche in Plano, TX. He's an honest, no BS person and a pleasure to do business with. I bought my first Box from him (an 01 lapis blue S) - we had a deal done in 3 phone calls and that included calculating my trade-in. He's in the top 1% of best car salesmen I've ever met. If he doesn't have what you're looking for, he can keep an eye out for you as their inventory (used to?) change frequently. His contact info is:
Toll free #: 877.996.1911
email:
dspeight@boardwalkag.com
Good luck finding your Box.
Terry