Houdini Hatch Seal

[floydraser]

I'm sure there's comedy in that title somewhere?

I just wondered if anyone has any recent experience of changing one of these seals? I've seen adverts for seal rubber which claims to be for a variety of hatches but I want to get it right first time. I'm guessing the default advice is to follow the instructions on Houdini's website, and that is to take a pic and send them the sizes etc. They don't give an indication of the price though, unless I've missed it. 

[Karizma]

We replaced ours a couple of years ago - got it from Seals+Direct Ltd. We got the 'Houdini A/B bulb seal' - pretty simply to install (self adhesive strip on one side) and worked a treat.