Not Yardley, but you have Tanner's on York Road in Jamison (although with the current gun climate, you might need a number just to get in the door) and "Bow For It" in Wycombe. Bow for it is an awesome shop, well worth the 20-25 minute drive from Yardley.
Just check the website first, he has limited hours.
Dan Neebe(bow for it) is well worth the 25 minutes. He will sit there one on one and have you shoot paper tune etc...without a line or rushed(with an appointment) usually he can work something out with you if he's busy.