So To date it, I would need a better picture of the Case marking and any marking that may be on the other side. Based on what I can see though it is probably 1940-1965. A good resource for case knives is the case website. As far as restoration, if you wanted to, you could likely do the blade yourself, taking high grit sandpaper and steel wool, and slowly removing the rust and polishing it back to its original luster, or whatever finish you desire. As for the handle, my honest opinion would be to remove it and have a custom knife maker put a new one on. If you really want to keep it original, similar bone can be found. Normally I would offer to do it ( you can see some of my work at gatorforgecustomknives.com ) but right now I'm swamped. Check the local knife makers associations in your area, or if you want to do it yourself, much of the supplies, including the bone slabs, can be ordered from Jantz Supply or Texas Knifemaker's Supply. Hope this helps.