The cam companies grind the cams for standard displacement engines, normally the larger or most popular sizes of the company there grinding it for. For small block MoPar guys, it is based around the 340.
Will a standard off the shelf cam work well in a stroker, Yea sure BUT when you have one custom made by a real cam guru, oh boy is it so much nicer.
When you speak with the cam company on the phone, be honest and leave nothing out. No secrets! The results will be worth every penny.