It will probably be difficult to find a CCW type holster for most handguns with a rail mounted light. It is harder to conceal and not that popular from what I have seen. I've seen duty type holsters designed for rail mounted options, but not any true concealed type. Are you looking for a IWB or OWB type holster? There is always the custom made option.
I have contact info for a saddle maker/all-around leather working guy out past Burns if you want it--from what I've seen of his work, he could probably fix you up with something custom.
I saw a holster on the Guns and Ammo TV show that allowed the gun to come out the front and was used mainly for rail mount lasers. I have also been trying to find one as I have a 226 with a laser mounted underneath.
Try Galco or Fobus they make great poly holsters with the click in lock feature so you know it's secure. I dont carry a rail light on my P229 but I love the Galco holster Matrix 7 very sweet.
Found out that Streamlight made the TLR so it would fit in the same duty holsters as the Insight lights so the TLR1=M3 & Blade Tech makes a couple holsters for the P229R and M3 so hopefully one of them will work.
Ordered a case of 357sig TMJ ammo and after waiting a few months received a case of GDHP ammo in exchange cuz the TJM ammo is not avaible yet.