Barrel Gas Block Rust Prevention

[NewGunner]

After changing to a low profile gas block the front roll pin channel is now exposed and unfinished.

What would be the best product to touch up this area to prevent rust? Also, is there any need to refinish the rear roll pin channel under the gas block to prevent rust there? Thanks

[NewGunner]

After looking into it more, it seems that I can either use a bluing agent or one of the bake on paints like KG or Duracoat. Would I be able to put the upper in the oven (upper receiver and barrel)? Guess I'll wait to see if someone knowledgable is able to chime in.

[NiteQwill]

Yes, you an put the upper in the oven (minus any plastics of course).