n550 should be good. If you start somewhere between the n550 data for the Sierra 160 and 168, you should be fine. Otherwise, give Hornady a call and they can probably point you to a starting load.
N550 will be OK, but if you don't get what you want out of it velocity or accuracy-wise, try some Big Game. It is still available and works great in the 7-08.
Had great results today, 10 shots just under 1inch at 100m. Worked up to 43 grains at 2.935 coal no pressure signs but shot good so didn’t bother pushing it.