Oops, thanks for the catch. That is just a typo though, so the following price is still correct (500 * $0.25 == $125). Retail price per blade is $0.20 - $0.25.
I've thought about the price premium and think it could go either way. The blades from at least one manufacturer are already produced from a single ribbon before being separated, so the process to produce longer blades shouldn't be too different (hopefully!). And if there's a 2x premium, that's fine, if its closer to 10x I would re-evaluate.
