1500y is pretty far, not crazy but glass really starts to come into play at those distances. If you are shooting past 1500y to 2k yards many guys prefer SFP scopes, but if you are not building a dedicated ELR (Extended Long Range) rifle I think FFP would work better and be easier to operate. At those ELR ranges, premium glass helps a lot. Helps with mirage, and helps with repeatability. Thin reticles help also, as they will obscure less of your target. One thing to consider also is are you giong to shoot this rifle mostly inside 1k or mostly outside 1k. I do reach out past 1k with mine, but most of my shooting is 200y - 800y at smaller steel targets. My scope and rifle can shoot much further, but thats where we play our games and shoot the majority of our matches.

I think the Vorex Razor Gen 2 ($2500) is a great scope, the major drawback with it is the weight. Nightforce ATACR ($2300) is available in you price range but will only be the SFP version. The ATACR F1 ($2800) is the same scope with FFP, my only issue with NF is their reticles. These are both very good and very reliable scopes. Your Kahles scopes bump you up to around $3k. Kahles are nice scope, but have questionable durability (but are great for leftys!).

On the lower end $1k-$2k you have the Burris XTR II, the Bushnell DMR/ERS/XRS, SWFA and Steiner TX5i. The Burris XTR II (made in Colorado!) is what I am recommending to a friend now. it is a good scope and has pretty good glass, great reticle (SCR) and street price of $1000-$1100. The Bushnell is very reliable, very repeatable, but the glass isn't all that. The XRS ($2k) goes up to 30x, but you will likely not be able to use it at that magnification due to glass clarity and mirage. The Steiner looks good on paper (and made in Colorado) but the first batch did have some tracking issues. The glass was pretty good, not S&B glass but not bad either. They have the SCR reticle (Special Competition Reticle) like the Burris. Steiner is now repairing these scopes for free and will mark the turrets on repaired scopes, once repaired these should be good-to-go. I personally owned a SWFA 5-20 HD and it was a terrific scope. I think the glass is great and the tracking is as good as it gets. It is not perfect, the focus knob and magnification ring is too stiff and the reticle is a little thick at max power. Great scope, maybe not the best for ELR though. Another is the Razor Gen 1 5-20. This is another good scope and will be in your price range. the turrets are good, the reticle is good, the glass is good enough. The Vortex warranty is the best, definately a good option. All of these scopes have Zero-stop (except the SWFA & DMR) which are nice to have.

The next step is a big one. Schmidt, Premier, Kahles, USO, Etc. These are the best you can get. But... if you shop around and mabye buy used, you can get one of these top tier scopes for $2-$3k. Might be worth it if you really want to get a great scope. Mile High has a deal going right now on S&B 3-20x50 for $2750.