The main reason I mentioned the Pedersoli is because I cannot find a SxS flintlock, brand new, that I can afford. The few that I've been able to find started at 3K and went up from there. Hell, even the used ones that I found that were worth looking at were almost that expensive.
Darren
You could always try building one. Prior to finding the Ketland, I'd found a percussion double that fit me OK and shot fairly well (for me--I am a lousy shotgunner). I had planned to basically copy it, only as a late flint gun. I was looking for barrels when I found the Ketland.
As I recall, I traded the caplock double, the case I'd made, a Dixon powder flask and a leather Irish shot flask, and some other stuff, and some cash (~$100) for the Ketland. I did have to do some work on it: replace the missing hammers/frizzens/frizzen springs and some other minor stuff, but all told I was in it for less than $1,000.
Given my predilection for shooting round ball from smoothbores (and my horrible wingshooting skills!) I could probably do about as well with a single-barrel gun. Maybe I should try building a single along the lines of a British late-flint park rifle, or watch for a deal on a used Pedersoli Mortimer.