1974 could be a very good guess. The decals are right for 1973/74, the goofy serial number seems to be right for 73/74 and that x on the bottom bracket matches the ones on my 1973-74 Raleigh Gran Sport.
See, check it out. I'm not sure why these marks were on the bottom bracket shell, but it seems to be on bikes all within a specific time frame:
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