My step-son was given a trumpet a few years ago by his grandfather. It has a stylish letter "B" on the bell with the letters USA beneath it. The only other nomenclature are the numbers 70810001 along the valve assembly. Can anyone tell me for sure what brand and model this is and what sort of value it has? The boy is now playing a baritone and a sax so he would like to sell this trumpet and doesn't want to list it for more than it is worth. Thank you all.