If I were in the market today for a good, reasonably priced AR-10, I would take a good look at a PSA version, especially when on sale, or with a "blem". They get very good reviews.
I dont have one, but have built 2 AR-15's off their kits in the last year, and have been impressed with their quality to dollar ratio.
I have a .308 DPMS ORC that is also a nice budget AR-10, but they are now out of business, I believe.
For a scope, I would look at a 1x6 or maybe 1x8 scope with an illuminated reticle. Can be used at 1x with both eyes open like a red dot, or zoomed out for longer distances. Vortex "Strike Eagle" series are good buys for the $$. Again, PSA often sells them on sale with a Vortex mount included.
Wanted to add, R/E the DB AR-10, a friend bought one about the same time I picked up my DPMS version. Both in the seven hundred dollar and change range. His looked well made, and had a free floated forend to boot. His has proven accurate, but he only has maybe 100 rounds thru it. My DPMS has maybe a thousand rounds thru it, and other than a gas block that came loose and had to be realigned and tightened - no issues, and accurate. My Armalite AR-10t is a nicer rifle than either, but should be for twice plus in price.
Larry