Well, since no one else chimes in.... My set up is not the same as what you mention and I have never own a Remington.... But depending on when do you want to start using the rifle, you might be better off building your own from either a new or used 110 savage action (I have done it both ways) which is what I did. If you want to use it this season (assuming yours end in jan 1 or close to that) then you will have to buy a package, however if you can wait to use it for next season building your own is very doable.
I shot a 110 Action with a SAV-2 trigger, Brux (SSS) 7MM RM, 1-9, 26", Varmint Barrel fitted with a SSS Brake. The scope is a Leupold VX3 4.5x10x50. I shoot inside the 300 yds (longest kill was over 300 but close) and almost every time I can see the deer go down thru my scope. Now, my rig is a whooping 14 lbs so that helps too. Our hunting is similar to what you describe, out of shooting boxes in a power line ridge.

The msrp for that LRH was over $1k although I am sure in reality it might be cheaper...

A 110 action (from a donor rifle) will run you around $250 to $300. (sell here what you dont need from the donor rifle)
A good quality barrel with a brake will be around $350
A boyd stock ( I have 2) will run your around $100, add about $30 if you bed it yourself (if needed)
A SSS trigger will run you about $100 BUT if the action you get comes with an accutrigger then you can save that.
A match recoil lug $25 (might as well do hat if you are doing all of the above).

Yeah, you will be close or over your initial expense but you will have a rifle that will shoot way beyond the 600 without problem and accurate! When I do my part this gun shoots about .6 at 200, with 2 round touching each other. Since then I have make the group smaller but not consistently, probably shooter problem.... That has the potential to do under 3 inches at 600 yards (depending on shooter probably better)... You cant buy the piece of mind that a well built gun (for the budget and use) will bring a shooter. I know when I pick that gun that if it is a miss it was all me...

good luck with whatever you decide....