It was pitted in only one area- that leads me to think a sweaty palm print or such, and that was the ONE small place that didn't get wiped down.
I'm another who would like to recommend against storing the rifle within the case.
I don't know what the rifle means to you, but those pits can be cleaned up and re-blued- but to do anything to make them disapear would be either way more expensive than re-barreling.
Speaking of re-barreling, you might google up a list of replacement barrel makers, contact them, and ask if they'd have a factory take-off bbl they would part with for a reasonable price.
For preservation and rust prevention (like we have a lot to worry about here in the Tx Panhandle), I find that plain old medicinal mineral oil works fine for my needs. It's in the pharmaceutical section of any Wally World down in the "I can't poop" isle with the laxatives.
Rednecks... Keeping the woods critter-free since March 2, 1836. (TX Independence Day)
I'm going to use the words "clip" and "Long Colt" every chance I get. It grinds my gears to see new members attacked when we all know dang good and well what's being refered to.