Western Illustrated Stories #9 appears to be a reprint of Gunfighter Library #7, with an all-new Keith Chatto cover.
Gunfighter Library #7 is the first $0.30 cover price issue of the series. According to Ausreprints, Gunfighter Library #6 was published in 1972, which places Gunfighter Library #7 in 1972/73.
Western Illustrated Stories #9 is dated 1974.
I'm not sure if there is a further issue in the Gunfighter Library series, but I wouldn't be surprised if there is another reprint of this issue under another Page Publications title.