I take it to mean ur talking about the seal that goes around that lip around the door aperture?
If so, the 850 seal is a standalone rubber with a metal insert which just pushes onto that lip. the basic shape is like.. this-->
UO... where the U is what fits onto the lip. The U is also the bit with the metal in it, while the O bit is hollow and is the actual seal part. BEWARE: These do not fit on australian 1964-on minis, they are too fat.
The later type as fitted to Deluxe, K, Cooper S etc, consists of two parts. It is basically like a
S shape, where one hook of the S into the lip, the other obviously faces outwards, and then a cover strip is put on top of the lip and is secured into that upwards facing part of the S. It sounds very complicated I know but i cant explain it any better!!
Here is a pic of K style... hopefully u can understand. As for pricing, i can only guess that the difference is A) prob come from england, B) metal inserty thing. The later type (provided u have the cover strip) could just be bought by the length from any rubber seal supplier.
