The indusrty standardized on the 7/8-14 thread for dies many yrs ago. The Lyman 310 series is an exception and there are some gigantic cases that require larger dies. The H&H based magnums and 06-308 cartridge heads and all handgun cases are dies based on the 7/8-14 thread dies. Lots of interchangable dies by many manufacturers. There can be some problems with old shellholders in thickness and you can move the case shoulder back too far causing head space problems. A rule of thumb is use the same brand shell holder as the die body, and watch the case length and datum line dimensions. You'll need mic's for this and any good precision measuring instruments you can afford. Get a good reloading manual, Lyman 47 or 48 is a good start and read the getting into reloading section and find a friend or advanced reloader for additional help.
The answer to your first question is yes, but the second question's answer takes precedence for reloading starters. If you got the Rock Chucker presses, the will last forever and they should be a good start.
Reforming cases is not cut and dried, so get the basics down pat before you attempt it. A hundred 7-08 cases can be had cheap compared to consequences of improper sized and reformed reloaded cases. Good luck.