Alright. I received the "mystery item" It is a MP44 magpouch repro from Kelly's Military in Massachusetts.
http://kelsmilitary.com/kelleys_web_site_056.htm
The good news is that the item works very well. The pouches are a snug fit around the body of the 40 round magazine, but the pouches are a scosh too deep. No issue there, a sandwich bag with packing peanuts pressed down into the bottom of the mag pouch cell keeps the magazine from going in there too far.
The bad news. Personally I think these are sort of dorky. They are very well made of heavy canvas and leather, and for those who seek the WW2 sturmgrenadier look replete with coal scuttle helmet and all, these would be great. They come with two separate pouches, each holding 3 curved magazines, and should fit on any belt around your waist, one pouch to a side.
I'll keep mine and see if I can figure a way to make maybe one side of the assembly work right as a chest pouch or something.
In sum: They are very well made, and hold the longer 40 round magazines for which there is no readily available pouch. They come in 3 different colors too. Price is very reasonable especially when the quality is evaluated.
There you go.