Never heard of Pendleton Ammunition. Nice to have another name for custom ammo.
Yes, a Rem long action will work, but it will need some rail work if it is not a RUM action. The fat case on the Nosler cartridges won't feed through the normal narrow rails. Might not need to open the rails if you go with a centerfeed magazine. RUM magazine is needed along with follower if you stick to the Rem BDL or ADL setup. If you go DBM, centerfeed magazines for a .300 Win should work. I didn't go that route.
Mine is built on an original 30-06 Rem 700 action. I opened the rails, opened the bolt face, and kept the BDL setup using a RUM mag box. Holds 3 down. It is a 1:8 twist and will stabilize all but the super long monometal bullets. Hart barrel, Manners stock, Shilen trigger. Sweet shooting rifle.
Not a difficult conversion, but it does limit what the action can be used for in the future unless you stay with a centerfeed magazine.
Jeremy