I'll have to check that one out! There used to be a good shop in Stone Mountain (Stone Mountain Armory?), but they closed a number of years ago. It was really before I got into black powder, but as I recall, they built custom MLs & carried a pretty complete inventory for the traditional ML enthusiast.
I went to David's Gun Room & Bass Pro on Thursday. Needed some BP solvent, patches, brushes, and a Hot Shot nipple for my Hawken. I couldn't believe the lack of traditional gear! David's had almost nothing for the traditional crowd....sad, considering he almost always had ML gear no one else carried. I found patches, but no decent BP solvent nor .50 brushes. No 1/4-28 nipples at all.
I finally found 2 Hot Shot nipples buried on the shelves at Bass Pro Shop....the last 2 were being closed out for $2.99. Needless to say, I bought both of them!