Glimmer Wing Ploomette: $12
Glimmer Wing Daisy Dreams: $8 - $10
Honeybuzz: $15, maybe a little more with her accessories.
Sunny Rays: $5 - $8 This is a tough one because it looks like she's been sold in various lots lately, all for under $20
Snowcatcher: $15
Flitterheart: $20
Wedding Cadance: $15
This is all I could come up with at the moment, just quickly looking at sold listings on eBay. The prices you have already for some of the brushables look good to me, though.