While I understand your desire to stay with made in the USA - and I respect that- in order to do that you will probably end up in the $300-$450 range. There are some Maxpedition packs that fit your price point and size needs, and are damn near bomb-proof, but unfortunately they are made in Taiwan.
The sleeping bag analogy used earlier is pretty appropriate here unfortunately.
You might want to start looking on the used market.
A little insight about the RAID packs as far as sizing goes- on the Original RAID (I have a MJK and a 3 color Desert) there are two zippered-mesh pockets that are attached to the lid/flap and they to protrude a bit into the main pocket area quite a bit, that might be why the pack appears to be so large physically, but has such a "small" main compartment size rating.
I can tell you that my 3 color RAID has been to Afghanistan several times and spent more time outside the wire with me than any other pack. I attached a claymore pouch to it, 3 mag pouches, and two small side pouches and was never hurting for space. Even for 3-4 week long missions.
I also had an issue with the way the shoulder straps fit/rode, but I grabbed a tube of Shoe Goo and layed a good layer on the straps and never had another issue with them slipping or not staying where I wanted them to.