window handle

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.

I need to replace the handle on a uPVC window – something I’ve done numerous times before. This time, however, I cannot budge the plastic cap covering the screw in the old handle. I’ve tried everything: a knife blade, blaming Brexiteers, swearing, blaming Remainers, and even prayer. But that...