There should be a model designation on the tang below the Schrade Walden logo, a number followed by "OT". "34OT" perhaps. Once you know the model number, you can look on eBay to see the current value. In 2004 Schrade went out of business and the prices haven't really stabilized yet.
At first there were thousands of Old Timers available at surplus closout prices. Also it seemed as if vintage OldTimers were coming out of the woodwork, perhaps if sellers were trying to take advantage of the demand and interest. Now there are fewer for sale it seems and prices are climbing, some models in particular.
Although I can't guess the value of your knife without knowing the model, I can tell you the factors that affect value. If it's used, the value is greatly dimished. The older Schrade-Walden tang stamp does make your's a bit more desirable. Is it a model that was made for only a couple of years, or is it a rather common model made up until the very end? Knives with the original packaging and paperwork sell for significantly higher than loose knives.
Once you find the model number, you can search the Schrade Collectors Forum at this website for more info - years of production, history, name, etc.
Best Wishes,
-Bob
