I know you said "kit", but right now PSA has a Freedom dissipator upper for sale for only $209.00.
http://palmettostatearmory.com/index.php/catalog/product/view/id/17499/s/psa-16-mid-length-freedom-stainless-steel-1-7-dissipator-without-bcg-or-charging-handle/
Just got mine in the mail yesterday...
It's mated to a Anderson Mfg lower with a PSA lower build kit. It's a 416 stainless 1/7 twist barrel. I know some guys prefer the Chrome Moly barrels. The upper doesn't include a BCG, but there are plenty of affordable one out there. I ordered a Wilson Combat BCG for $108 shipped on sale. AIM has their BCG on sale right now for $75 shipped.
If your looking for a whole kit I know Del-Ton, and JSP make a kit. Most rifle kits run just a hair over $500, but they include everything to build a stripped lower into a complete rifle.