Although Ido have quite a bit o C&O, much pre-1970. I've found that rolling stock is not that bad to find. Engines, on the other hand, can be an adventure. Even teh Chessie System tagged products seemed to be ll B&O.
I think that Monon and Wabash are much harder to find. With the restoration of a couple of Berkshires, the NKP has come to be a bit easier find. For a LONG time, I was buying undecorated stock and applying decals. the difficulties I was having was one of the biggest reasons I purchased a decal program for my computer and started making my own decals.
I do find the whole scenario a bit hard to understand since C&O was a big coal drag road and many like to model "coal roads". But, you may be correct in stating the deal with CSX. But, Conrail owned some of the C&O rights along with CSX. Clinchfield was another hard one and still is.
One thing I have noticed while traveling and visiting various hobby shops in other regions is that roads found in those alien regions are more apt to carry the "fallen flags" of those areas. I visited a shop in St. Louis a few months ago and found nothing but western roads. No NW, NYC, or Pennsylvania, ACL at all. But if you wanted Santa Fe, Southern Pacific, or BNSF, you were definitely in the right place there.
Bob