The last set of 14"s my friend with all the cars just bought, when he decoded the date of mfg. on them, they were more than two years old. If it were me I would have just used them, not him, he took them back and made them find another full set of four that were not as old.
depending on how much you drive /year....I dont mind buying 5 yr old tires, if I get 35-40k out of them the next 5-6 yrs...I wouldnt drive on 10 yr old.... If I recall correctly , in Sweden they forbid selling tires 10 yrs old.