Hi EC,
When mini-mag lights first came out about 30 years ago I bought one but could not find a pouch for it. So I fashioned one out of a section of seat belt and I am still using that pouch today. My aunt worked in a factory that made seat belts and she provided me with the small spool of nylon tread that I used to sew it. About 2 months ago I saw the same spoool of thread in a mini-repair kit for tents. The only trouble is that the tent repair stuff was brown tread and you would probably want black.
Good luck,
Mike