evansb - well done - close enough for anyone but a pedant.
However.....
Pitcairn didn't make things easy as.....
PA-7 Super Mailwing 1929 (ATC 196) = 3pOB; 225hp Wright J-6; span: 33'0" length: 23'9" load: 1129# v: 135/155/57 range: 520. POP: 2 [NR213M, NC684E].
Pitcairn PA-7M [NC876M] (Frank Tallman coll)
PA-7M Super Mailwing 1929 (ATC 196) = 1p PA-7 as mail plane. POP: 10 [NC94W, NC351V, NC378V, NC545K, NC825N/826N, NC876M/877M, NC7967].
Pitcairn PA-7S [N95W] (K O Eckland)
Pitcairn PA-7S [NC13158] (Frank Rezich coll)
PA-7S Super Sport Mailwing 1929 (ATC 196) = 3p sport version of PA-7. $8,500; POP: 16
PA-7S [NS53W, NC54W, NC68M/71M, NC95W/97W, NR213M prototype, NC824N, NC10375/10377, NC10379, NC13158]
The Civil Aircraft USA registry has it listed as...
NC 13158 Pitcairn PA-7S
You have control, evansb.