Most any Italian model 1861 Springfield is very barrel heavy compared to an original. If you ever have handled an original the difference is startling!
Dixie Gun Works did/does sell a model 1861 made in Japan by Miroku that is the closest non-custom made Springfield available that best resembles an original. These are no longer being made, and only kits are now available from Dixie in limited number.
The '61 is the most accurate Springfield for use in most all threaters and impressions, 1861-1865, while the model 1863 does not show up until later in the war.
Just my opinion.
Steve Sullivan