As James says in his review, I think this is a bit of a "pot noodle" of a kit, using bits & pieces Italaeri had lying around. If the figures are the same as the old 75mm howitzer kit, they do indeed date back to the 70's, & they were originally Esci (rather like the Italeari "new release" Sturmtruppen & Rest Area). Though old they aren't absolutely awful, but interestingly from the painting point of view, the original Esci box showed them in the Heer splinter pattern camo (there was a Heer smock, but it had an attached hood & it did not have elasticated cuffs). The new kit box is wrong in every respect, the front shows the M1944 "pea pattern" suit, this is not what the figures are wearing. They wear the interesting mix of early camo smock & gaiters. The back is pure fantasy, so anyone buying this kit & intending to keep the figures needs to do their research.
It's not completely impossible that this gun was used by SS troops; even the first line units got some "transient" equipment up to 1942(e.g. the original Marder III with the 76.2mm Russian A/T gun). There were plenty of second line SS units which used a lot of captured material (e.g."Prinz Eugen"& "Politzei" which were never first rate, & the Eastern European Volunteer Legions). The units raised later in the war did much of their training on obsolete or foreign weaponry (I have seen photos of "Hohenstaufen" training on Russian or Czech(?) howitzers, which have to be drawn by the men themselves!), before being issued with the latest German equipment for combat.
"Lord Raglan wishes the cavalry to advance rapidly to the front, follow the enemy, and try to prevent the enemy carrying away the guns. Troops of Horse Artillery may accompany. French cavalry is on your left. Immediate. Airey."