The Pak 36 was just released by Rubicon, and soon the Pak 38 and Pak 40 will be available. There is even talk and a few teaser 3D drawings of the famous 88mm Flak 36/37 that may (or may not) be released.
But what about other AT-Guns from other countries? Will there be AT-Guns for American, British, French, Italian, Japanese, Soviet Union, and other military forces?
There are lot of AT-Guns that can be recommended, but some possible good choices that come to mind because of good support (lots of other miniatures available), and also they are not available in plastic are the following:
American 37mm gun M3
American 57mm gun M1
American 3-inch gun M5
British QF 2-Pdr
British QF 6-Pdr
British QF 17-Pdr
Soviet 45mm Model 1937
Soviet ZiS-2 (57mm gun)
Soviet ZiS-3 (76.2mm gun)
QF-6pdr + 57mm gun M1:
The good thing about the British QF 6-Pdr is that it can be marketed as an American or British AT-Gun because the 57mm gun M1 was a very close copy of the British QF 6-Pdr. I'm sure Rubicon can catch two fish with only one hook with this kit. By making the kit with the option to assemble either the British QF 6-Pdr and/or the American 57mm gun M1, this would make it very marketable. And maybe the extra bonus bits to make the American Paratrooper version of the 57mm gun M1. Lots of potential for this kit.
Zis-3:
The interesting thing about the ZiS-3 was that the Germans used many captured Russian 76.2mm AT-Guns until the appearance of of the German Pak 40, so this can be marketed as Soviet or German.
Soviet 45mm AT-Guns:
Some of the early Soviet AT-Guns might be easier to make into a kit than having to start from scratch because the Pak 36 was produced under license by the Soviets in 1931, but they later decided to mount a 45mm gun (45mm Model 1937 AT-Gun) in place of the 37mm. Essentially, it is a Pak 36 with a 45mm gun tube. More experienced modelers should be able to convert a Pak 36, but what about crew figures?