Hmmm... Doesn't look like you have a response yet. Have you looked into previous posts from time past and found out what you need to know? I think most of the info you desire could be gleaned from there. But if this helps... The slide would be etched as you describe, because the blueing was done outside the factory. Obviously, if things got separated in the blueing tanks, they could be matched back to their frames. (The same would be done for most stainless slides later on, so that after going through the blaster, even though blasting was done in house... well, you get the picture).
Barrels sometimes had numbers on them too; sometimes not. When it came to coned barrels, everything from military surplus to Colt National Match barrels were purchased, cut down, and coned. The cones would be chrome plated on the outside. The barrels only had to be gov't spec to be put through the process. It didn't matter who manufactured them originally. When the company couldn't get enough stainless one-piece barrels for production, they would resort to the old process of coning again. As such, sometimes you'll find two piece "coned" barrels in one piece slides and frames.
Hope this satisfies your curiosity, ...Deeton