Don't ask me where, but I saw a browning hi power in great shape for 500. It would have been hard to walk out without it. Sorry still no help for your problem may have made things worse.
I'd go with the 700. Be nice to have a good long range rifle. But then your saving money for the scope, so it wouldn't be complete with just the rifle purchase.
I would invest in more ammunition to sling out of the barrels of my currently owned calibers. Or the Rem 700, and I'm not partial to owning a rifle (except maybe a cheap ol' Mosin Nagant)
Aimpoint Pro and use the rest on ammo. Like others have said, the new rifle will make for the need for a new scope and new ammo. Glocks are everywhere and you already have one. Finish you AR before going a new route.