Unchambered 45mm and 47mm barrels are in stock in SFI and Kuryaka's etsy has the red anodized 13mm 40mm barrel in stock as well.
No. the stock barrel isn't chambered it can work with non chambered barrels.
Unchambered 45mm and 47mm barrels are in stock in SFI and Kuryaka's etsy has the red anodized 13mm 40mm barrel in stock as well.