I actually do have all my files on Shapeways, but not for public release. On Shapeways the cost per set would range from $35 to $95 per set of dice depending on what level of detail (determined by material, based on which service they send it to for output) and that includes $0 profit for my work, and $0 for packaging or shipping costs. It should also be noted that the type of 3D printed output you get from Shapeways is more suited to that sort of print-on-demand service, and doesn't have the extremely high level of detail and finishing that I'll be getting from the service bureau that's handling my mold positives. Their rates are considerably higher than Shapeways (more like around $250-$300 per set of dice) and the results are very precisely machined so the molds for the final product will reflect that high level of detail. It will definitely make much more beautiful dice.
As they are currently specced out, the HYDRA dice are also a bit larger than the common dice you'll find from companies like Chessex, Gamescience, Koplow, or the Armory. Their typical d6 is about 0.5" per side, and mine are about 0.8" per side.
The reason you sometimes see cheaper sets on Shapeways is because they make all the profit from the product, leaving little to none for the designers. They also primarily produce dice that are hollow, taking advantage of the capabilities of 3D printers to make objects that can have cage-like structures. The reason these are cheaper from Shapeways than my dice is because mine are solid, not hollow. If I designed them to be hollow for 3D printers, I'd have to make a hole in them to release the supporting material 3D printers use to make hollow structures. It would make an inferior product.
HYDRA dice will be made from high quality plastics, slightly larger than normal, and they will be available in custom colors and a variety of styles.