10mm is pretty much universally expensive, and I doubt if Dick's would ever
carry it. The cheapest I've seen is the Blazer TMJ from a few
online sources, but even that is expensive.
If you really want to do 10mm "right", you need to reload... its the only
way to shoot it without going broke.
In Dick's ads they usually advertise Was / Now / Case (10+ boxes). I would assume .223 and 7.62 would be no different than .38/.380, 9mm, .40SW and .45.