Was having a browse round tesco last night in northampton as you do and found these....
Faux leather stool with chromed steel frame. Adjustable height. Minimal assembly required. H68xW40xD49cm. Black and White
Assembly: Minimal assembly required
Chair Type: Stool
Features of Product: Extended height 88cm.
Frame: Chromed steel
ProductDepth: 49 cm
Product Height: 68 cm
Product Width: 49 cm
Seat Colour: Black or White
Seat Material: Faux leather
This is instore only and direct link will give different price!
may be store specific.. this was in northampton.