June of 1997 - If you change the O (letter) in your serial number to a 0 (number). You can look up any Rickenbacker serial number on the RIC website at www.rickenbacker.com. Go to the Service tab, and click on Serial Number Decoder.
Kevin: Rose-Morris guitars (like all Rickenbackers) were built in the same factory in the USA. They were built to meet specs set by Rose-Morris in London in the early 1960's. They had decided to offer a limited line of Rickenbackers, all finished in Fireglo with Accent tailpieces and F-holes. The twelve-string RM1993 model was unique in that it was double-bound with dot neck markers, an F-hole, and trapeze tailpiece. This tailpiece was replaced by the 'R' on later production.