I'm wondering if it isn't later that '71. If my memory of numerous trips to the Databook and Archives serve, that's a P-13-9 from the period after the significant changes to that model were made in the early 70s: 3/8-inch shorter chainstay; more gradual curve to the front fork, especially toward the dropouts; top-tube cable clips rather than under the top tube braze ons. Until those changes were made, I believe the "racing" and "touring" Paramount frames of the late-60s, early 70s were identical. I thought those changes were made in '73, but in any case later than '71 -- but maybe I'm remembering incorrectly. Easy enough to determine: did anyone write asking for the SN?
Lancaster, PA, USA