FBO distributor advance limiter plate kit pricing question

[Duodec]

I've seen these recommended online, so went to look at them on their website.

The plate by itself is $39.  The kit that has the plate, and three pairs of advance springs jumps to $61; the set of 6 springs adds $22.  I get the plate but is that really the going price for six distributor advance springs?  Sticker shock is a frequent occurrence in this hobby, but wow...