Forster or Redding dies, and I would spring for the micrometer seating die in a heartbeat. Why? Because getting the seating depth right affects accuracy SO MUCH, and only with a micrometer die can you vary that depth easily. Totally important for long range work. Personally, I like the Forster seating die, and I use redding bushing dies, but I am not sure you need to go bushing right off the bat. You can sink a lot of money into bushings, and that rabbit hole of neck tension, case wall thickness gets deep fast. Just a good FL die, set to bump the shoulder back .002.
To verify that bump, you will need the Hornady case comparator, as others have suggested. AKA Lock N Load headspace guage. Your 7 RM belted cases will last a long time if you only bump the shoulder .002. 7 RM is a great case, don't let the guys with the "newest shiny thing" tell you otherwise. Proper sizing will have your 7 RM headspacing off the shoulder and not the belt. Down the road, if you get the dreaded bump before the necks split, you can invest in Larry Willis' belted die base resizing tool. But you don't need it now, for sure.
I'd also put in the plea for a beam scale. Why? Because a beam scale is analog and virtually fool proof. It is your reference tool to keep the electronic scale honest. I personally find that with the heavy extruded powders that you will use in a 7mm RM, I get .1 to .2 grain variation with my Chargemaster. I set my Chargemaster to throw .2 less than my desired weight and then trickle up on my beam scale. For work inside of 400 yards, totally unnecessary. For long range stuff, I think it matters.
Powder trickler -- save the change and use a 12 guage shotgun shell. You put 100 grains or so of powder in it, and tap tap tap. Little practice and you tap out individual powder granules. Just remember to return the powder to your can after each loading session.
Another bit of "buying advice". Buy 8 lbs of powder. Why? Because there is a lot of variation in powder lots, and once you have duplicated that special load that your gun likes, you do NOT want to start over again after 1lb is gone. You WILL have to experiment with loading to duplicate that custom load. Especially if you want to use 1x, 2x, 3x fired brass. The sweet spot may be close to the loading they gave you, but I doubt it will be identical, as many others have suggested.