You are right about the rarity of holeters, other than 1950s style police holsters for the Astra. What's a Zooter Shooter to do but build his own. I modified an old 1911 gi flap holster and into a crossdraw too. The Astra fit the 1911 holster but was way loose, now it's a tight fit. The belt loop is a tight fit on my foragers belt too. I moved the brass pin lower and lowered the flap but kept the embossed US. I had thought about lining it but that was too much work as ratty as the holster was. I haven't figured out what to do with the old brass pin hole, if anything.
I also fished an old aftermarket 1911 leather dress officers flap mag pouch out of my junk drawer. The brown holster and pouch match pretty close. It also has an embossed US on the flap. The Astra mags fit it fine. I did have to remove the top two copper rivets to get it on my forager belt. Need one more mag to complete my Astra project. Got a bid in on one now.