There are probably several guys on here that can switch it back to Pill lock.
The parts would have to be hand made to fit and aged to match the rest of the gun, but pictures of original pill locks would make that a straight forward deal.
As for destroying the history of the gun,,, what history? ,,,, As is, it's just another percussion conversion. Any value the gun lost was lost when it was converted from pill lock to percussion.
The gun won't be worth any less with a good reconversion back to pill lock, and will probably be worth a bit more.
If no one answers you, email me and I'll send you a couple names.
Some pictures of the gun would be great! Did you buy this rifle at auction, for not a lot of money? If so, it'll probably cost you as much as you paid for the gun for the reconversion.
John