As stated it's nothing special, no offence, however, it's worth what someone will pay for it, obviously. What I mean is there is a huge market for retro frames at the moment, so if you can face the fact that whoever buys it will probably strip it and convert it to a fixed gear, then you should have no problem getting in the region of £80ish via the likes of
eBay.
What you really need is a guy who had the same bike in his youth, and who would love to buy one again to re-live the experience. Rose tinted eyewear is a sure fire way to squeeze a few extra ££'s out of something like this.
Good luck with it what ever you decide.