What is this time of door/window seal?

[noobiediyer]

I need to replace some of the seals on my rear door. This is what the cross section profile looks like (camera was not focussing properly so sorry for the blurry photo):

Just to show how it fits in case it's not clear (red edge is what gets jammed into the door/glass gap to hold it in place, blue edge is what is visible when it is in place):

Does anyone know what kind of seal this is and where I can get it from? I had a look on Screwfix, and various other sites. None of the window/door seals they sell have this kind of profile.

Thanks in advance

 

[crank39]

Search for wedge gasket in Google, there's a multitude of thicknesses so be prepared to do lots of back and forth with a tape measure, seller's on ebay sell sample packets for 99p and you see which fits best and order the correct one