It is unlikely that you will find a precarved stock for your Pedersoli rifle unless it is from Pedersoli for big bucks and you probably won't be able to specify stock grade.
Your best choice is to call a stock supplier, such as Pecatonica or Tiger Hunt. Other suppliers can be found in the ads in "Muzzleblasts" or "Muzzleloader" magazine. Tell the what you want to do and what quality of blank you want. You will probably be offered a Hawken blank with the barrel channel and ramrod hole drilled. You will need to install the lock side bolts, triggers, trigger guard, barrel tang and buttplate.