You might even try getting larger sizes (or even men's jerseys) and have the sides taken in. Tailoring shouldn't be more than $10-20 and mens jerseys come in a much larger selection of styles and materials. I am 108 lbs. and bought a men's Castelli jersey in small. I had my mother and her magical sewing machine take it in and you'd never guess it where it came from.

Plus... have you noticed that men's clothing goes on sale much more often than women's? Blargggh.

P.S. I have a hard-to-fit body too. No boobs, actually. Tailoring is the panacea!