Post a link to that page with parts or what year bike you looking at?
Squeeking noise is normally caused by a combonation of brake dust, and glazed over shoes and drums. Just take it appart, and lightly sand or scuff the shoes at brake surface and the drums. Also clean it out real good. Grease the cam post/shaft wear it goes through the hub, and the flat sides of cam lobe that opens shoes. Thats all that's needed. You only need to replace shoes if worn. Otherwise, you just wasting money. New parts squeek as well once dusted up and glazed. This is all part of preventive maintnance..... Mine squeeked very loud until I did this when I replaced my sprockets and chain. Water from riding and washing just causes this to happen quicker. Light rust also causes a squeek..... Every 500 to 1,000 when it starts queeking again, I remove rear wheel, inspect, clean, scuff, grease shaft & cam... Good as new again