Can these seals on my opening lights be replaced

[Mr M]

Most of my PVC windows are in relatively good condition but some of the black seals on some of the opening lights are starting to perish, become brittle and fall away. Not on the window that I have photographed below. It was just the easiest window that I could photograph to use to try to show which seals I was referring to.

I haven't tried to remove any of the existing defective seals yet for fear of causing further damage to them but do these seals just push into a recess in the white frame of the opening light and if they do, can they just be prised out and a replacement seal of a similar profile then be pushed into the groove? I assume when the windows were originally manufactured the white frames were extruded and welded together and the black seals that I now nwwd to replace were fitted after that but I may be wrong?

 

[crank39]

Yes they look like they pull out most likely a bubble gasket but there are various shapes and sizes, look underneath the opener for the joint and pull a bit out and snip a bit off, then have a look on eBay or the like and buy a sample bag, find the one that fits best and order it by the metre