All upperline Deering and Vega banjos come with a serial number sticker which states the serial number and model name. This sticker is located on the inside of the resonator on resonator banjos and on the inside of the rim for openback banjos.
Goodtime Series banjos say “Goodtime” on the peghead which makes it easy for you to tell if it is a Deering Goodtime banjo and not another brand. When you see Goodtime Special on the peghead, that lets you know that the banjo has a tone ring in the pot assembly; that is what distinguishes it from the non-tone ring models.
The best bet is to send pictures to info@deeringbanjos.com. We will be happy to review them and help you find out what banjo you have. Please send a front view of the peghead, a front view of the fingerboard, a front view of the flange and side view of the pot assembly. These critical areas will give me the best idea of what you have in hand.