Tom, how is the rifles serial of your PPCo scoped P.14 rifle marked on the "ears" of the receiver? With or without a W suffix? And engraved or stamped?
And when you compare your two rifles, is there something they share in common? Like do they have an additional serial number somewhere on the stock? Are they both with the W suffix to the serial? Looking at the rifle here: WWI P14 Sniper photos Forgotten Weapons it appears that this is also a PPCo scoped P.14 sniper, which is in the US (and it features the serial number in the wood, in front of the magazine guard), plus the stock not sanded. I wonder if this one would also come from Interarm? Does this company still exist and do they have a serial number list of rifles they imported?
Edit: these are the PPCo/BSA scoped rifles from the Bruce Stern collection, sold by James D. Julia auctions in 2008:
*US MADE WINCHESTER P14 SNIPER RIFLE
*US MADE WINCHESTER P14 SNIPER RIFLE
*US MADE WINCHESTER P14 SNIPER RIFLE
*US MADE WINCHESTER P14 SNIPER RIFLE
All of these four have the square type front base, so they all appear to come from the Irish contract.