I see no-polepiece mini humbucker pups on eBay all the time. I wonder how different these Gretsch pups are, to the sometimes ridiculously cheap ones online... not that I want to dissect a “good” one just to see what’s in it.
Pretty hard to tell from a chrome soapbar cover. The original Gretsch 2202/1222 series had a pickup designed by TV Jones but built by Gretsch, probably on contract somewhere overseas. It's a good pickup and they show up on Ebay sometimes. I think I have a spare as well. Gretsch used to note that in some of their product descriptions, but now they are simply described as "...Gretsch mini dual-coil bass humbucking pickups."