Yeah baz aparently you can fit them if you change the inner cam bush -b50 and later b44 use a bigger diameter inner journal ,b50 timing gear is thinner so you have to thrust it as well ,as you said they come up on US ebay a bit but just putting the feelers out locally first, i have a couple of std b40 ones, one is rusted the other has some pitting on one lobe not sure about using it-cheers
