Dawson,
I don't think anyone can provide an accurate account of what this gun will ultimately cost. But, some of the swags from earlier were thought to be 'ballpark'. They ran from around $7k to $10k for a gun without engraving.

I'll stick my neck out a bit again and take another swat at it.
figure Ken gets $100k invested in start-up costs. I figure 100 guns total might be a realistic estimate, but it might be half that number. So figure $1k to 2k worth of amortization,
$2k to $3k for the action
$1k x 2 for the barrels = $2k
$2k for stocking labor
$200-700 for checkering
$500-1500 for wood
$1k for fitting and finishing the barrels and action (blueing, casehardening, etc)
$0 to $?K for engraving.

So, I'm thinking around $10k without engraving. Ken may be far enough thru his planning to provide a more accurate swag.