SOUTH AMBOY - The owners of a South Amboy accordion shop are experiencing an unexpected resurgence in sales. Accordion-O-Rama has been in business for more than six decades, having moved to South Amboy 10 years ago. Owner Peter Shearer, who runs the business with his wife, says younger musicians seem to be rediscovering the instrument. He says the accordion is not as popular as it once was, but that the increased sales are always welcome. Shearer took over the company from his father, who launched it in 1950.