Personally I hate destroying ANY old part because, hey, you never know what the next guy will need. If this gun is actually used for a decoration, just how likely is it that it would chamber a modern 10 guage shell--the 3 1/2" Magnums generally available to the public, not a "short 10" which are much harder for the average guy to find?
If the barrels are stout enough it would be fun to shoot. One could purchase a set of 10-12 Gauge-mates and shoot 12 gauge Wnchester AA Low recoil/noise ammo through it.

I modified these (with thanks to homeless jOe) by grinding the lip away at the split so that I could pull the shell out with my fingernail, leaving the Gauge-mate in the chamber.
Steve