I don't recommend buying a new stock for the gun at all. You're putting way too much money into the project. Besides, if you use the same lock, you'll still be faced with the issue of replacing the missing hammer and the option is to buy an entire new percussion lock. That's $75-100.
You can file off the underlugs on your own. You then silver solder a barrel rib and drill them for thimbles/pipes/ramrod holders. When fitting the barrel rib, you might want to alter the fore-end of the stock for more pleasing lines. Afterward, you can refinish the barrel yourself by browning it.
You can file off the underlugs on your own. You then silver solder a barrel rib and drill them for thimbles/pipes/ramrod holders. When fitting the barrel rib, you might want to alter the fore-end of the stock for more pleasing lines. Afterward, you can refinish the barrel yourself by browning it.