I would go local for as much as possible. That can eliminate a problem with wrong parts, phone calls, shipping time/cost etc. All the ball collar items and packing come in 1 set. Mount can be rebuilt (less expensive) Be sure to take clutch/pressure plate to parts store to match, a new pilot bushing/bearing would be in order. If tranny oil isn't migrating to differential your torque tube seal is probably good. An "okie" bushing is normally used to replace the seal& bushing at the same time. That said some items may need to be sourced on-line. Here's a link:
http://chevy.oldcarmanualproject.com/shop/1948_51truck/index.htm
