I've got a Uberti Colt Navy 1851 in .36 cal and I love it! - looks pretty too. Sparks, smoke and flash all depends on the powder charge anyway but it flies out of the Navy with 24g (even more with 28g but I wouldn't recommend two many of those)

Quite pricey new but expect to pay £80-125 in a Gunshop but often cheaper sold privately.