Hi, Your sax was made in 1919, serial # 50,000 was at the start of 1919 and serial #58,000 at the start of 1920. Unfortunately, you Conn sax is NOT a B-flat Tenor but a C-Melody Tenor which plays in the Key of C just like a piano. That is what the letter "C" stands for. L is low pitch which is standard tuning. The C sax sorta faded away by 1930 as home entertainment changed from live music to recorded/radio sounds. Depending upon condition (dents, finish wear, broken or bent parts, etc) $250 is not a bad price but to get it playable will cost you about $450 plus shipping expenses unless you have someone ggod who knows vintage saxes. I used LoKey for my recent C sax overhaul. Fine job, quick service. I assume your sax is silver plated as most were back then. Tom