I have two of them myself, not very powerful, but nothing wrong apart from a little outdated and odd design. If I remember correctly they are a crossflow design without any baffle or piston step, which explains the low power...

The value is very hard to estimate, the right (or odd) collector might be willing to pay a lot, while someone looking for a small glow engine to use might not give it much value. My guess would be around $60-90, mainly because of the pristine condition and box etc. But I'm not a collector myself...