Just replaced the split seal on my fridge lid on my 2008 39i. These are available from Jeanneau dealers still, I got mine from Ian at Clarke and Carter for £20 inc tax and postage, so relatively good value.
However things like this may go out of stock in the future, so I cut the old profile (2nd pic below) and did a search for fridge door profiles. Lo and behold what looks exactly correct is available from Scotland: www.sealitscotland.co.uk/general_profile.php Reference Arrow Head JME-322-C. Crude measurements also tally. Might be useful for someone in the future
As well as splitting the seal had slightly perished in the moulding, so when pulling out left some bits which are hard to remove - the moulding is quite thin, so take care. The seal seems to simply push back into place - no glue.
I was also looking for replacement seal on-line and it looks like there is another producer near me which also produces vacuum plates for custom made refrigerators if someone is perhaps interested... en.turna.si
On our 379 we found that the attachment of the fridge box to the underside of the counter was not level, resulting in a leak in the door seal on one corner. We glued thin plastic shims to the offending low areas on the inner counter lip and added a continuous ribbon of freezer tape glued all around the lower counter edge. This has worked well for five years. As belt and braces, we added a 3/8" high density foam mat, cut to fit the entire counter above the fridge. It really holds the cold in the fridge as well as providing a good non slip surface when washing dishes.
Will definitely need to research a bit more, the boat is in Spain and the cabin temperatures are getting to 30 degrees during the day and the fridge is struggling to get below 11 degrees. I guess the water temperature won't be helping either as i'm sure its got a cooling plate on the hull.
Away to buy a mat that I can cut to put over the surface to help with the insulation.
A few weeks ago someone posted their new improved fridge seal which eliminated the problem of condensation and icing of the freezer compartment. And they included a picture of the seal (which I recall was bigger / thicker than the original). I've tried searching for the thread and pic but can't find it.