It is unusual that they would choose Barlow for the signature. It does match his signature that I had found examples of. Do you have any idea on value of the knife. I found the configuration in other brands but not Boker.
I would estimate 1920s-1930s. In that time frame there were several companies that would put your name on the knife handle for a fee, individually or a bunch of them (you could give them away instead of a business card, for example.) Remington is probably the best known. So, they would use some process to transcribe a facsimile of your signature onto the finished knife handle surrounded by a 'resist', and then acid etch it to etch the name in the handle -- or do the signature in the resist to leave the name in relief after etching. We did an article in KNIFE WORLD last year, I think, about how Remington marketed such knives.
I don't consider myself a Boker expert but I did research and write the article on Boker history and markings that appeared in KNIFE WORLD. If you'd like to send along some photos I'd be happy to look at the knife.
Hey there, David! Welcome to iKnife! Come on in, kick back and check things out. There's some handy tips on our front page to help you find your way around, and some fantastic people in the Chat room if you have any questions or want to shoot the breeze. Site rules are also on the main page, and if you get creative, you can customise your My Page to suit your own style! Hope you enjoy your stay with us! Great to have you on board!