No. 4 MK 1* Safety Question

I have a 1942 dated No. 4 MK 1* produced by Long Branch that I would like to restore to operational condition. One issue I have is that the safety assembly is missing. In doing a bit of research on the Sarco website, I discovered that there are four variations of safety assemblies available. My question is which variation would be correct for my Long Branch, the 3rd variation: Mid WW II No. 4 MK 1, early Long Branch No. 4 MK 1 or the 4th variation: Long Branch No. 4 MK 1* Fishtail? I'm thinking the 4th variation, just seeking confirmation,

I keep banging on about this but in the REAL world of REAL Armorers shops and REAL riflemen as opposed to concourse exhibitors then the shape of the locking lever part is totally academic. It's not as though some are cheap foreign made pattern parts (although I suppose some could be.....). They were ALL made to fit and operate safely on the rifle.

Others might have different opinions