Try and get a few of these notes, as ones produced for parts of South Wales, who tried the same sort of business venture, are now highly prized, and quite valuable.
Certain businesses in Swansea produced similar banknotes around five years ago, the £5 note goes for anything up to £50 if you can find one.
Not many were produced, and the venture did not amount to a great deal, but the notes that were printed, are highly collectable, if you can find any for sale.
I did a quick internet search, but could not find any.