Roman, I've thought about Gossens already. Easier to get, about the same price, but rather large and not as sensitive as this one. Also, they usually have issues with old mercury batteries.
Brian, I know that this one looks like the seller want to pump up the price... Others I've seen were usually in $50-$80 (USD) range. Those are really good meters.
As for adapting something else, I don't think so. This is not really an area where I'd resort to DIY solutions

I need something relatively small and portable, which I can hang around my neck or stuff into a small pocket. No point in having a meter which is lager than a Leica

I've thought about MR meters, but I really don't need one. Those are not any better than my Weston, and the only benefit is that you put it on the camera (making it bigger, heavier and clumsier).
Maybe in the end I'll get a Gossen Sixtomat digital - a friend has one, and it's very sensitive. Not small, though
Denis