Miranda --
Castelli makes some lightweight warmers (lighter than the Shebeest ones, actually). Look for the "Lycra Warmers" (not Nano, thermoflex, etc). I will warn you that the men's small armwarmers are a bit baggy (I also find the shebeest armwarmers in small a good fit), but I would think the leg warmers might be fine (I think there's generally less difference between men's and women's legs than between men's and women's arms).

These are the ones, I think:
http://www.bikesomewhere.com/bikesom...364/3348/23246

It's a nice weight.