Glock 19 and Sig P229 .22LR conversion kits?

[BoilerUP]

Can somebody point me in the direction of an online retailer that has the Advantage Arms Glock 19 kit in stock?

Alternately, anybody know why Sig differentiates their .22LR P229 conversions between railed and non-railed frames?

I have an older P229 40SW that does not have an accessory rail on the frame and would absolutely LOVE to get Sig's threaded barrel conversion for a suppressor...