Like the original Brass Steam Dome cover, the story goes that the tooling to form the RW1 Open Wagon body was lost. MSS did introduce an open wagon but it has a wooden body with coal effect load.
The RW1 comes up regularly on eBay UK, and are very popular thus commanding good prices (the RW2 Lumber Wagon usually go for the cheapest) but likely most have excluded posting to North America in their listing, hence you are not seeing them on eBay.com -
http://www.ebay.co.uk/sch/i.html?_odkw= ... n&_sacat=0
The wheels (mazak) are pressed onto shouldered steel axles so you need different wheelsets to re-gauge to 45mm.
The MSS rolling stock kits are the same as the original Mamod ones, but are in slightly different colours to the originals. The tender was introduced by MSS (open body on the flat bed wagon).
Chris Cairns