Record No 52 Vice - Quick Release Spring Profile

[Metric]

Hi Guys, I currently have a much loved Record 52 vice that has has a broken quick release spring, as Record parts are pretty scarce in this part of the world I was wondering if anyone had a scaled 1:1 photocopy or reasonably scalable photo / hand sketch of the required spring profile in its untensioned state, I have about a third of the original spring to work from and have found a spring works that can wind a new one but just need a guide. Any suggestion / input much appreciated.