I've seen photos of your Rutland car on here before Dave, and it is very well done. All the single and double sheathed cars readily available in O have steel ends when wood sheathed ends were just as (if not more) common, so your Rutland build and my build here should really stand out.
I think you are also correct on the convention cars - these prototypes were done in resin by a company called East Wind Models. I have been looking for one of these kits on-and-off for about five years now, and I think in that time only one has come up on ebay for well north of $100. I decided I'd rather just make my own at this point, and besides, what better material to make a wood boxcar out of than actual wood?
~Chris
