If caplock is ok, look for a used pedersoli double barrel in 10 or 12 gauge. They are pricey new or used, but that second shot sure comes in handy (pedersoli doubles seem to go for $450-$600 used). You can also find CVA double barrel caplock shotguns on Gunbroker for less than a pedersoli. I hear they are quite functional, just fit and finish may not be as good ($250 -$450 on Gunbroker). The india made muskets are hit and miss from what I've read. They can be functional if you are willing to work with them a bit. Personally, like others here said, I wouldn't spend my money or time on them. You can also save some money by buying an Indian Trade Gun kit (Indian, as in American Indian). Several sites online sell kits and finished Trade guns (try Dixie Gun Works, Track of the Wolf, etc.).
This message and signature were both made using 100% recycled electrons.