Under the saxophone museum tab on this site, there is a serial number list.
This site is full of iinformation, so just look around.
The concertine, or concertiono C melodys were made by conn, but you will not be able to find any info from that particular serial number sequence. If it is identical to your CG conn horn, it is either the same time frame of shortly afterwards. After Conn would upgraded to a new key design. Straight neck etc. the older model horns were what Conn stenciled out from their extra in stock saxophone parts. I have had old model conn saxes that were stencil horns and they had the newer upgraded pivot screws, a newer design in and around 1923.
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