Simon, I replaced both leaking seals on my B37 2006. i don't have any specs but pictures are attached. I replaced the original grey seal with 3mm x 26mm neoprene rubber strip (search on ebay). This was non-adhesive. I suggest you measure your portlights first but I think a 10m length is adequate to replace both seals.
To remove the portlight unscrew the 24 screws on the top. Then gently ease the edge up with two large flat-headed screwdrivers, starting at one corner slowly working your way round - a bit like removing a bike tyre. if you have help get someone to push up the portlight whilst you do this. It will take some time and effort to break the seal. Once removed, clean every surface. The new strip can be pushed into shape and there are nylon lugs you can use to hold it in place although for some reason these do not go all the way round the portlight. Overlap and cut as necessary to go round the corners but note that the neoprene is pliable so you can 'bend' it as necessary to help get a good shape. Cut around the fixing points as necessary too. Once you have made the new seal replace the portlight and push the strip into shape before securing down again. Fit and seal the screws and the securing slot for the perspex frame. Trim as necessary.
