Here's an old and helpful thread for some insight. heads up though, most springs aren't available anymore that you see on the chart unless you find them second hand.
This thread was created as a guide for the 3rd Generation Proteg Community. Enjoy and feel free to PM or eMail me with questions/comments/suggestions/complaints.
*The Mazdaspeed Protg springs are manufactured by Racing Beat. The Mazdaspeed Protg spring rates are slightly revised (stiffer) than the MP3’s due to additional shock valving and a larger front sway bar(?).
Springs such as B&G, Goldline, Sprint, Progress Group, Tanabe, Evotion, Falken and Intrax, as well as coil-sleeves such as Skunk2 and Tom Motorsports should be considered...