Re: Where to find the right holster for my Iver Johnson revolver???
I thought maybe a holster from the Hunter company might work but didn't see anything in their size chart that has a front hinge like your Iver. (Webly, Enfield, S&W Russian or Schofield) They still might be an option if you can find a store with a good selection and they let you 'try them on'.
They are traditional looking and aren't fitted as much to particular models as are most leather holsters. Reasonably priced too.
I haven't dealt with custom holsters but I'm sure one of those guys could fill your bill for the money. I bet one could make you a reproduction holster if you could find a good picture of one like that Navy issue.
Good luck. If one of my granddads had passed down a treasure like that I would want a propper holster too.
Warte nur, balde ruhest du auch.