It took me a long time to find a glass shop that was willing to replace the seal on my 1971 250 C. Glass shops are not skilled in dealing with the seals that have chrome strips in them, etc and it is important to find someone who DOES have this kind of experience.

I would only by an MB seal.

I would find an OLDER glass shop who has people who have been there for a long time.

If you have the option of new glass, do it at the same time, but on my 250 C I re-used both the front and rear glass.