1890's Iver Johnson" covers a lot of ground in the way of different models. Obviously the bore is pitted, and maybe the chambers too. It may or may not be in working condition. In other words we don't have enough information to give you the answer you are looking for.
Most gunsmiths won't work on them because fixing one is labor intensive, and at today's labor prices few people are willing to pay the necessary expense.
If you can identify the exact model, you will find some, but not all parts at
www.e-gunparts.com
All things considered, I suspect if you took the money to fix up the revolver you have, it would be enough to buy another one of the same kind that was in much better shape. I see that as a better way too go.
I should also add, if it was made during the 1890's or early 1900's it may not be safe to shoot with ammunition that isn't loaded with black powder. Guns of that age were not intended to used with smokeless powder. You are apparently talking about a revolver that's likely over 100 years old.
I have figured it is a second model so i did know about the whole blackpowder deal but i like that you guys are trying to help but i wanted to know if it was possible not the problems around it i thank you for your input