I can't find the specs on the speakers to find the exact size, so you will want to measure them first...

these may work.

http://www.speakerworks.com/2_inch_speaker_repair_kit_p/swk2.htm

really the only way to fix disintegrated speaker surrounds is to replace the surround with new one. did this on a set of speakers at home (bought 'em new in '94, foam went around 2009 or so) really easy to do, just have to take your time.