I'd pay that no problem since it already has Magpul grips and stock. Too bad I picked up an AR locally here on Father's Day for a little over $400 more.
I got one of those piston driven Ruger SR-556 AR versions. Just a little over 100 rounds so far, but really happy with it. They feel like a regular gas operated, but are way cleaner.
I put my duty carry request in today so I hope to get the OK next week. Not that I'm unhappy with my assigned Bushmaster M4, I just like new and better toys.