As scrap, they're worth about a buck a pound (though with good strong scrap metal prices you can get a bit more - I think locally our range custodian got $1.75/lb for our range's scrap about a month ago).
A .223 case weighs about 100 grains and there are 7000 grain per pound, so 70 pcs. of brass per pound. The 1,000 pieces would be about 14 pounds, so figure on getting $15-$25 for it at the scrapyard. This is only 1.5-2.5 cents each.
You're probably better off selling it to be loaded. It's good brass, but it is extra work to deal with since its primer pocket is crimped. I think you could quite fairly try to ask 10 cents per piece for it.
The 7.62 might be worth 10-15 cents each, but the fact that they are mixed headstamp is a drawback, as is the fact that you only have a small bunch of them.