These 12-sided dice aren't regular dodecahedra. The're oddly wonky. But amazingly they are totally fair. That's because they are isohedral, meaning every face can be mapped onto every other face through a symmetry of the object.
These objects have a handedness. Which is to say the mirror image of a dice is not the same as the dice! So here, you get a set of 2, the right-hand version and the left-hand version!
Also check out the skew d6s.
Price = (the 141st prime number) pence = 811 pence = £8.11