No catalogue number on sleeve or label, it comes from the runout.
Runouts are etched in very small letters, particularly on side B of the 7.

500 copies were pressed in the US and shipped across to the UK where the sleeves had been printed.

Glossy laminated sleeve with Warsaw printed on the spine.
On the rear of the sleeve, the laminate falls short of the edge on all sides, except the spine (by about 2mm.)
On the front of the sleeve, the laminate only falls short on the right hand side opening.
All 500 copies of this sleeve came with this defect.
Some distinctive hickeys in the top left corner of the pulsar design, some copies have a tiny white circle pressing error on the front:
https://www.joydiv.org/wswocover.htm

Other noticeable differences, when compared with later editions, include: different ridge widths on the labels of both LP and 7.
On the LP, the outermost ridge extends all the way to the edge of the label.
Also, the titles printed on the label intersect with the ridges at different positions to those seen on later editions.
This copy also has very short run-off grooves, matrix numbers in small letters.

A1 to B5 were recorded for a first album scheduled to be released on RCA Records, but which never saw the light of day.
C1 to D2 feature their first Peel session, recorded 31st of January 1979.
C1 miss-named and given as Excite One on the label.
Matrix / Runout: RZM - 200 - A (Runout side A)
Matrix / Runout: RZM - 200 - B (Runout side B)
Matrix / Runout: RZM-100 - A (Runout side C)
Matrix / Runout: RZM-100 - B (Runout side D)