One thing, taking your time to spell and properly set up sentences will go a long way. It'll help us be able to help you, and when its a jumbled mess like that it just makes things a bit hard for us.
Anyway, from what I 'can' understand, i'll try to answer the following.
There should be Tightbore barrels made specifically for the m700 somewhere out there, see if you can come across A Tanaka barrel as the KJW m700 is a clone of one. Im pretty sure there is a person that makes barrels for it somewhere in the states, but i can't remember his name. Do a bit of Searching I suppose!
As for the bolt? Don't paint it, or you won't be able to move the bolt at all, the paint adds a thick layer on top and I don't think the gun will like that.
Though, why not keep the gun Black and Silver? Having a Shiny silver barrel and a camouflage body simply doesn't make any sense. Sniper rifles are sniper rifles. Not bling-bling show peices.