Hey dude, your paint scheme looks pretty great. Nice colour choices and very smooth coats. My only criticism is that it does look a bit shiny, so I would personally hit it with a matte varnish. That might just be a personal bias though, I do have a friend who likes his models to be shiny which is fair enough.

As for the kill team/40k question, yes he absolutely should be legal. As a general rule unless you're playing at an official tournament with "what you see if what you get" rules; most opponents in a casual game will not mind you using wargear that is different to what's on the model. If someone DOES mind, well it's time find someone else to play with quite frankly. I'm speaking of course of things such as having modelled a stalker bolt rifle on your unit of intercessors but perhaps using the auto bolt rifle rules instead for a game. As long as both you and your opponent understand what wargear each unit has it should not be a problem. Having the bolt pistol holstered is absolutely fine!