I don't think the wandering zero complaint was to make an excuse to go to a semi-auto rifle. They didn't for another ten years, if that was true. But nevertheless the No 5 continued in use in the Far East until the SLR was finally available for issue, and in some case was used alongside the newer rifles (as well as M1 carbines). The No 4 continued not only in use but in production almost until the SLR was being produced. But that was true for the M1, too. One would have to think that, given all that were manufactured during WWII, there would be plenty on hand but maybe wars are hard on things.