Been shooting and hunting with the 280 AI for 35 years, currently have 3. Used to be you had to make your own ammo, blow out the brass. The 7mm SAUM is a great cartridge. The 7 mm SAUM was getting hard to find before all the shortages here in the northeast, just like the standard .280. When shelves were full it was easier to find 280 AI than 7mm SAUM and std 280.
I have seen numerous elk killed with 160gr bullets like the Partition, Solid base, Barnes X. I've seen moose killed with the 150 cup and core. Antelope and deer with all kinds of 140's. I have a 6lb 280 AI and 8 lb 280 AI, one is easy and one kicks a bit. The platform you choose, mostly the stock dimensions and barrel contour will help you find a comfortable shooter.
One rifle I have is a M700 re-chambered from 280 std, the factory barrel is 24" and produces lower velocities than the other 24" 280AI's by 150-180 FPS, I get better velocities and groups from Hart barrels.
I've never shot a suppressor on a hunting rifle, they mitigate some of the recoil I assume? Also, it's no surprise I have always gotten better performance from longer barrels I have all 24" barrels and a 26" wouldn't be out of the question, just don't go shorter than 24".
Someone mentioned "longer shots", run the numbers at "Shooters Calculator" to be sure it will do what you want at the distances you want. It will probably be within an inch or two drop of any 7mm except the Weatherby or STW.