With the increased popularity of pistol caliber carbines, Palmetto State Armory has been leading the charge for affordable options and components. The latest addition is their new AR-45, available as a pistol in 8” and a 16” carbine with several different hand guard options. The lowers use Glock compatible double stack magazines, and I’d suggest finding some expanded capacity magazines to make the most of it; the standard 13rd magazines are going to be swapped often once the fun starts.
Like most of PSA’s pistol caliber offerings, you can buy either a stripped lower, complete lower, complete upper, or complete firearm. The lowers are currently 7075 billet with an anodized finish, and the complete lowers come with a KAK 10oz buffer and milspec parts elsewhere.
If you’re wanting the fun of a KRISS Vector at half the price, take a good look at the new .45 offerings from Palmetto State Armory.