Depending on the barrel shape, you either have an 1851 or an 1861 Navy. If the barrel is octagon in section, you have an '51, if round a'61.
Either way, considering what you paid and what came with the revolver, you did just fine. These third generation guns aren't valued as highly as the second generation or "C" and "F" series guns. Build quality was very uneven, with some very nice ones and some very poor ones made. I've got a '60 Army that is extremely accurate, yet it is so poorly finished that it is an embarrassment to be seen with. I've seen others that are beautifully polished and blued and worthy of the Colt name.
As for firing it, you'll have to decide. Twenty or thirty years from now, an
unfired "Signature Series" Colt maybe a valued treasure to someone. Or
it may still be considered a poor relation on thr Colt family tree. There's just no way to know--I'd probably fire it--but I also fire my second gen guns too.