I gave $1,000 for it but it is a prototype (I traded in a couple of muzzleloaders to get the cash outlay down) and has some cosmetic sins. Doc is working on a .54 and I do not know what the price for that is. Honestly, I don't think they could afford to manufacture them for that price because of the expense of regulating the barrels. However, the thing that I learned with this rifle and if I were to have a custom double manufactured is that I'd insist that the bore diameter be .504 with 1:24" twist rather than most standard .50's if it were a .50. This gun will easily and quickly load .458 Hornady 500 grain Interbonds and 530-grain Powerbelt Dangerous Game Bullets, and .435 grain Buffalo SSB's and it is very forgiving of differing loads. I also am a firm believer in musket cap ignition in an inline rather than 209's because of the time it takes to dig 209's out and replace them. Musket caps are much quicker. But honestly, If I were having a custom dangerous game double made, I'd go with conventional sidelocks, double hammers, and musket cap ignition. Sidelocks are quicker to reload. It is easier to see that the cap is in place. It is easier to clean the nipples. Hammers let you know exactly where you are at in relation to the gun's readiness to fire. The gun would be more compact than all but the drop actions (like T/C Omega). I'd like something like the Pedersoli Kodiak with musket cap ignition, heavier stock or composite stock, synthetic ramrod, and the best heavy duty locks and heavy duty triggers that are made. I'd want the gun to weigh at least 12 pounds and be at the very least .58 caliber... but again with a slightly oversized bore for quick recharging and capable of handling a regular load of at least 200 grains of FFg. I'd think you'd be looking at a minimum of $2,500 for a plain Jane model but it would/could be a very effective dangerous game muzzleloader.