Nice set of wheeled vehicles!
An advanced product of Skoda Works: 7.5 kanon PL vz.37. Never fired in anger in czecoslovakian hands, but were important for boosting the AA defences of Italy and Netherlands (in Europe, in the Indies the AA gun was Bofors M29), and after the fall of Rome, also of the III Reich. And the 20 guns bought by Finland were pivotal in the defence of finnish cities during the Continuation War. Cheers.
NB1: I read several years ago about the dutch model, as a 3 legged mobile carriage (only one source), but I never saw a picture of it.
NB2: I am not sure about the resizing, because the gun looks so huge! My only numerical reference about the dimentions is the barrel lenght: L/48 or 3.6 mts. I mesured that lenght form de breech block to the muzzle brake. But the general appearence is of a very big gun (compared to other AA guns of the era, in FD scale). I will be very pleased with your help! Thanks.