They're somewhat legendary in terms of trouble dating them using serials. They used multiple styles of number and often added random letters to prefixes and suffixes on their numbers. The N generally stands for Nottingham factory. The location of the stamp also is a clue. What is most useful is using a mix of the hub and the decals/paint. The Raleigh serial number guide on the Sheldon Brown site is something I've never found very useful. It is one of the preeminent bike sites, especially for old Raleighs, but there have been some more recent innovations in registering serials for Raleigh Sports models.
http://www.kurtkaminer.com/TH_ralsport_visID.html
Kurt K at the Headbadge has put together a pretty decent guide to decals on Sports models over the years. Check it out and see where yours fits best. It does appear to be a 1960s model. The "6" imprint on the hub and your decals definitely seem to urge early or mid-1960s here. He also has done a Raleigh serial number registry, but it's still only somewhat useful because Raleigh seems to have been all over the place with their numbers/prefixes/suffixes.
Raleighs are also somewhat different in the sense that they seem to be manufactured "by era" rather than by year. Raleigh would put together a set of decals/paints/parts and make the same bike with those for several years at a time. Old American balloon tire models often would change from year to year like cars. Raleigh was more constant in that they would make the same exact bike for several years at a time. In that sense a specific, pinpoint year is nice to have but not as necessary with Raleighs because the differences year to year are less important than the differences in terms of the overall era of manufacture.