You got a fantastic value. The watch was one of hundreds ordered by Ford Motor Co. to celebrate exceeding sales goals in 1955, as referred to in the engraving on the back. It is a Memovox manual wind alarm watch. Very collectible. More information may be found here:
http://www.watchprosite.com/?page=wf.fo ... pi=3969446
What's even better about yours is that could very well be the original watchband, which is rare.
Zaf will know about current value, but if yours is working, then it's worth well over 10 times what you paid for it.
I need to go to garage sales with you.