Passed it several times and it was never open - just a sign stating "Open at 1500h" but it never was
The back of the shop opens onto a pedestrianised street (that's the Rue des Barres) with a couple of decent cafes - but the window there is full of artifical hands............ or hands from sales dummies
They also sell individual turbine blades (lot of Allinson's) for around 8 Euro