Burgo (HW) 55 project

I've got a mid-50s Burgo 55 that I need some help with.



The first issue is the front sight. Its missing the hood and the sight insert needs to be reconditioned. The dovetails are spaced at 8mm. Any thoughts on where to find / how to fabricate the hood? Any thoughts on the sight insert?





The next issue is finding / fabbing the barrel pivot bolt jam nut. The original is missing.



This is what it should look like



Can the top of a current HW jam nut be machined off to replicate this look?

Thanks

Mike