There are 19 " barrels available, they are few and far between. We have a couple members here and if you look over on CGN you'll find more barrels available and a man that assembles them regularly, Gunsdora...you'll find him here too. Not sure if Criterion offers 19" barrels. You won't find 18 1/2" barrels. Search for availability of 19" carbine barrels online and then a dealer to import it for you.

For the rest of you looking on, firearms here are either registered or they aren't. Either restricted or not. Many of ours are named specially so it doesn't matter if your AR has a four inch Walther barrel or a twenty two inch match barrel and no gas system. It's restricted and needs registering...there's so much more.