If you are looking for something in a dedicated suppressed role you might try these guys:

http://www.gmriflebarrel.com/gm-m64-...ith-1-7-twist/ ($167.95)

A Pencil Profile design in a 11.5" package, this 5.56 NATO barrel is chrome lined and phosphate coated. The carbine length gas block is .624" diameter.

You can always enlarge a gas port, hard to shrink one. LOL

I freely admit I'm a GMB fanboi. They are an OEM supplier to numerous companies and I've had nothing but good luck with their barrels.

I have to say, though, the one Sionics barrel that I own is definitely a shooter. And by the time you add a decent gas block - I use the Geissele Carbon Steel sold by ALG Defense - you are in the Sionics price range.