I collect Flight/Aeroplane/Flying Review and Pop Flying mags and also live near EGNX... but happily I'm not interested in any post 1970 magazines of any flavour. - So will certainly let you know if I come across any on my travels.
These magazines are becoming increasingly difficult to find, but they are there to be found if you persevere.... I don't use ebay so can`t comment on prices but postage rarely stacks up unless you're shipping a large number in one go.
Don't underestimate how much room they'll take up though if the collection grows..