Mine is No. 200280
Bought in a big downtown gunshop in St Louis ca. 1955 as a college kid for $45. Sent back to Ruger for a steel cylinder which cost, as I recall, $5.00. It also wears an aftermarket loading gate and hand carved grips. But I still have the original (somewhat battered) box, gate, olive cylinder and grips. Of all my Ruger, this is still my favorite!