double glazing window

Please can anybody tell me what time of handle this is or where I can buy a replacement. We can't close the bedroom window at the moment which isn't ideal with winter closing in. Any help would be appreciated.

Fellow forum users. This job started off a a simple handle replacement. Then I found the turning the handle does not open/close the latch, it's stuck, so now I'm trying to remove the entire window so I can take a better look maybe WD up the latch or something, to get it to open/close. If you...