The value of any item, is the amount you can sell it for! If you look on eBay, some times an item sells for, say $100 - this is because more then one buyer likes the item. If only one buyer likes your item, it could sell for $20. Ken.
I haven't kept up with the current market prices of this pattern. However, with a low serial number like "#17", it is most likely a salesman's sample of the Walden knife with the birdshead pommel. Condition will play a role as will completeness (all papers, packaging etc.). IIRC, those were carbon steel so prone to pepper spots and marks from acid fingerprints. So it may be a very desirable knife to the right collector. Possibly well over $100-150.
Bobj, without actually seeing the knife in question, we have no way of knowing if our guesswork is in any way accurate. Please show us the knife? Here is an offsite hosting utility that makes it quick and easy to upload your photos from your device. http://upl.co/
