You are right. The same number and scrawled signature appears on the little card tag attached to the cloth bag that comes with each Antiquity pickup.
Guess who just got off his arse and bothered to look at the SD pickup packaging?
The plastic-bobbined Fender single coil is definitely American. The polepieces on American Standard Strat pickups are normally of equal height. Also, the colour coding of the output conductors on middle position pickups is different to denote RP/RW. If your polepieces are staggered, the pickup could be from a Highway 1 model.
Some Duncan vintage-style pickups faithfully recreate the magnetic polarity of Fifties Fender pickups. This is different to modern Fender pickups. Hence, your combination of "vintage" and modern could result in positions 2 and 4 being neither hum-cancelling nor electrically in phase.
Solution - a middle position example of whatever your other two Antiquity pickups turn out to be.