Greenhouse glazing seals

[Remeboy]

Can any one help?
My Aluminium Greenhouse glazing seals need replacing, they originally are bedded in with "round strips of Mastic" on a roll but I am unable to locate any of that material at all. My idea now is to use one of these "Silicone sealants". When checking which to use, there appears to be that many on the market, all for different purposes, that it's quite a "minefield" to decide which would be best suited. Does anyone have any suggestions?

[Whoever]

Why don't you try contacting one or two greenhouse manufacturers and see if they can offer a solution?. Many of them will have websites and a "Contact us" facility available via the website. They may have repair departments who can sell you the material you need.
Google "Greenhouse manufacturers" or something similar and take it from there.