Hello,
I live in France and this is our understanding of the situation :
As for the R§S, Euroarms of America is the main supplier : it is available with fixed or dove-tailed sight, blued or grey finish, standard barrel (normal turn) or WALTER Lothar (the family of famous WALTER German guns)barrel (fast turn : stabilizing bullet) . Basically you can mix all these options to get the one you want.
Pedersoli market its own version but it is suspected to be based on Euroarm frame (with Lothar barrel) with additional manual gunsmithing attention : better trigger notably (Euroarm trigger can be quite stiff and necessitate some smoothing) . The price will almost double.....
There is also a German version made by Feinwerkbau which would be really different and very high grade but even more costly.
In case some basic kitchen table gunsmithing is not a problem, the Euroarm version is the best cost effective choice.
As for the Remington, Euroarms product the same choice of option as described above and probably the Pedersoli gun could be an improved version of the Walter barreled Euroarms gun.
You can check the barrel twist and sometimes a "N" or double losange on the barrel identifying the Walter barrel.
Anyway, all of these gun, even basic model are very accurate ( more than enough for my skill )
Bye