Was there a stem option referred to as "rainbow?" There is a seller on eBay with a set of these, they basically look like white trigger stems with a few splatter colors (pink, blue, yellow, orange). Just wanted to see if there were an original option or if someone splattered these.

There were the Rosa editions which were hand painted, so they could be almost any color really. Probably the rest of the frame broke, so the seller's trying to get what they can for the remnants.

Are they anymore rare than any other Blade parts?

Suppose since Blades only really came in solid colors otherwise.