Some list remington 9 1/2 mag primers, some list cci mag, and some list regular lr primers. I do not want to buy $200 in primers to load 7 rem mag. Can I just run with one choice?
Yes, since you are going to start on the low side of the load and work up you can use whatever. However I would use a magnum primer.
When I despair, I remember that all through history the ways of truth and love have always won. There have been tyrants, and murderers, and for a time they can seem invincible, but in the end they always fall. Think of it--always.