I think there is also a ''variation 4", the 'Friends of the NRA' version ;')
Since these pistols are relatively new to collectors, I doubt that there is any certainty on pricing.
The Italian contract is rare because the limited number made and shipped to Italy, I would expect.
Not enough serial # data available to determine how many of each variation were made, the numbers suggest that not much more than about 6000 pistols were produced. I tried contacting Sig-Sauer in Eckenförde, but no information there...
Somehow it is interesting that we can find out less about pistols that are 10 years old than on pistols that are 100 years old