Few if any. Perhaps some last maybe a tad thinner in the heel such as the JL 7000 or 8000 lasts but barely so. RTW is based on average foot sizes despite last shapes that differ. A certain heel width will almost always be associated with its corresponding ball width and length since most manufacturers seem to be using the same foot size scaling and distribution data.
What you want is a combination last which is most often MTM. Also my experience had been that heel widths seem to be getting bigger. I have a few 20 year old shoes that had tighter relative heel cups.
Corthay is one of the few brands that actually fits me very well; many have to upsize due to its universal narrow fit. Like you, archangel, I face the challenge of having a narrow heel and actually caring about how my shoes fit.
