Rear window behind the drivers seat

[gypo]

I just got me a sliding window to go behind the drivers seat of yellowbus on here (cheers mate) he was kind enough to send me the rubber with it. It looks used but ok, would it be ok to use this or should i buy new and if so where from, they seem a bit dear on jk?
Thanks
G

*E D I T* Oops just noticed this is in the wrong section, sorry Admin