Nice '68 C10. I had one once myself and yes I had to replace the rockers.
If I understand correctly your 250 will be your personal training engine in class. That means you'll have good guidance(I hope.) from your instructor(s). Rock Auto has good prices if you don't mind paying shipping and the time wait. I bet your local auto supply can price just as well and get same day delivery. Also, I would ask your instructor about obtaining parts through the school. Sometimes they strike deals with a supplier.
Welcome and Good Luck with your C10 project. Hope you share your progress here.
