1) unless someone fronts a lot of money, you wouldn't get enough volume to keep costs low.
2) i don't think SP is going to be able to produce the legend molds you want, regardless of cost.
3) that many new complex legends is going to be a huge pain in the ass to proof, to mention working out kerning and other spacing issues. assume you're going to need to run every legend at least twice through their CNC and then on top of that the modifiers will need to be proofed at least once