Saw this earlier in the Long Eaton store, Nottingham.
There was both the Z50's in graphite and pink. There was plenty of stock for both colours, only the Pink version being £4.50 I believe and the Graphite being £14.50. Ideal stocking filler at that price (pink variant). I would not pay any more than £10 for one of these.
Didn't buy it myself as had just bought a bluetooth speaker as a gift and this would have been pointless. Also, wouldn't be worth picking up and selling on eBay as there would be no margin.
Not sure if local or national. Went in the Toton store beforehand and don't remember seeing them.
Your mileage may vary