As suggested, pick a bullet, a similar load for driving them equally in each cartridge, run them through a recoil calculator and you'll have a reasonable comparison between them. You'll probably find that the 6.5TCU, 6.5JDJ and 6.5 BRM are going to have less recoil than those based on the BR or PPC cases.
Personally I think the mindset of putting a rifle scope on a handgun is questionable, even on a rimfire barrel. There are plenty of good handgun scope choices available that will easily do just about any kind of shooting you'd do with a handgun, including long range.
FWIW