It is hard to say the value, it is not uncirculated, but it is definitely worth more than five pounds. The value would depend on the condition and also the buyer.
In one hand, collectors pay a premium for solid numbers.
In the other hand if it has folds or tares or holes then, that would reduce the value. But don't try to fix it up. Don't iron it or try to remove any folds, that will just reduce the value. Try not to handle the note. Put it in a good protective sleeve and hold on to it for a while. As in a while I mean 20 to 30 years. Yeah I know, but with age comes value.
It is very hard to tell the grade from a photo, this may help you get a rough idea: http://alphanumis.blogspot.com/2015_10_01_archive.html The closer to UNC the higher the value.
The best way to find the "Approximate" value is to take it to as many dealers as you can. But what ever they offer Do Not Sell to them!!!!! Remember if you sell to a dealer you will most likely get less than if you sell to a collector. Once you get some dealer prices add 60% to guess at the LOW value number and you will get a general idea of what a collector MAY pay for it.
But it is more valuable than 5 pounds could be more than 100 you will need to do more research to feel the market.