This is mainly for the UK members, as I’ve noticed a lot of people have been trying to track down MV lenses like myself, the only place I found was www.discountmodels.com in the US. But they were very good, and arrived about a week later as they only order in only after orders are received. They do a conversion chart from railway scales to common AFV headlight sizes, and a quick google for MV lens will get the sizing chart.
Here in the UK I’ve also come across a specialist headlight lens manufacturer, they seem to be a clear resin with the lens refraction patterns molded in. Might be an alternative to MV.
http://www.scalelink.co.uk/acatalog/Accessories.html
Hope it was of some help and not teaching people to suck eggs[:)]