Patience grasshopper, patience... There's a fellow who posts here that does professional gun case restorations, maybe you could have him restore it or possibly get some advice from him. Sorry, I can't remember the mans name.
Below is a "Chicago style" gun case I made for fun seven or eight years back. Since I wasn't able to match the original blue liner material, I chose a liner material that was a complimentary color.
I think I purchased the material at Hobby Lobby, but I'm not sure. It was a fun project and easy to do.
Steve