i could possibly get you the aa polys if you want let me know. also im also doing custom 3 way i am doing 8" kicker ssmb8mavin soft silk tweets and mavin dome midrange. i realy like these mavin product they are the shit . awesome product
http://www.mavin.com/index.php/products/mavin-high-performance-dome-mid-range-speaker
http://www.mavin.com/index.php/products/mavin-high-power-high-output-soft-dome-tweeter-75-watts-rms
http://www.crutchfield.com/S-qUl2d2XIK5u/App/Product/Item/Main.aspx?i=2064SSMB8
For a midrange?... no dice. Fs is 480hz which means you'd be crossing at at about 900hz at least. A true midrange should play ~200-3k, give or take. But, at the least should pick up at 300hz and play up to 3khz. imoEDIT: also how to people feel about these midranges?
http://www.madisound.com/catalog/product_info.php?products_id=547