I'm pretty sure that some people are looking for these, they show up occasionaly on ebay, but are $55 + $7 shipping or something like that, I just bought a set from here, 47.99 plus free shipping (got very quickly). Just thought I'd share, and these are the covers for the power mirrors not the xl and stx mirrors, I'm putting a set of power, turn signal mirrors on my truck soon. Enough of my rambling here is the link, enjoy.
TFP Chrome Mirror Covers