I also have a 7 mm rem mag in a mauser 3000, I did not want to spend over 500.00. I bought a Nikon Monarch 6-24x50 sf, bdc from ebay used, it came with the orginal box, all instructions extended turrits for 450.00 in like new condition, to my door. I decided on nikon monarch because I have a set of Nikon Monarch binos for bird watching and that is the go to set of binos at a moderate price for bird watchers and the glass is excellent, as I have compared them with other high price ones and they are the best buy for the buck out there.
I just got to the club to shoot Saturday and used the scope and I was by far very happy with the crispness of the glass and the entire scope, also has 1/8 " clicks
both Nikon and vortex are great for the money. For the ranges your talking about I wouldn't waste money on turrets. a simple mil-dot or BDC reticle will do all you need. If you think that you will want to push it to say 7-800 yards the turrets are very nice. In that case I would spend the extra doe and get a vortex... and a little more yet for a PST. 2.5-10 is all you need for 800 yards.
Vortex. I got a low end swarovski ($800) and replaced it with a $400 Vortex. Better glass. Hard to believe, but the Euro brand scopes are getting a run for their money. On the very high end i think euro may be better, but on the mid to low end they are very crappy. Compared to nikon? i can only talk about bins there and Nikons were a nightmare. went back 3 times and still bad. Vortex has an awesome warranty too. No fault.