Difficult to say. The rulers should say 'star wars' and 'may the force be with you...' But these could have been wiped off due to age.
I got mine for £45, which was a good price but it was in a lot better condition.
They are made by a company called 'helix' that made some of the first items for the franchise and were exclusive to the UK.
Helix items fluctuate a lot on the market, mostly because people don't mark it as 'vintage Star Wars helix' and instead lable it as 'star wars pencil case'. So there are lots of bargains slip through the net.
I have seen 3 of these on eBay this year. If I was you I would also be willing to sell it worldwide as foreign markets are liklely to target UK exclusives.
This item I would say, considering the condition -£30. But I have seen one in great condition go for £125.
I would like to see other opinions on this.
Some other helix items have gone for a lot more.