Your hyd. rollers are can be reused on a new cam, but how many miles have you racked up on em; that would be my main concern...
If your not planning on reving past 5500-6000rpms you shouldn't have to worry about a thang!
But then again, it certainly won't hurt to swap out the old ones while you're in there. One less thing you'll have to worry about!
Ultimately it's up to YOU
Good Luck!