Water Spaniel,
I've seen a few project Darnes recently in the $600-900 range. I'm guessing you have one of these. I wouldn't spend too much more money on this one. Here's what I would do (and not do):
Cylinder choke in the right barrel is perfect for lots of upland hunting. I'd leave it as is. I would just get the safety fixed (and maybe have someone polish the bores a bit) and call it good. Buy yourself some RST 2 1/2" shells and go shoot some birds. If, after having had the gun for a while, you decide Darnes are the cat's meow, you can buy a nicer one. If (like me) you decide the Darne safety is a pain in the neck and you can't get used to it, you're only out a few hundred bucks. Just my dos centavos.