Supercoach commenced in season 2005, highest recorded SC score since are:
262 J Brown (2006 Rd7)
254 G Ablett (2008 Rd5)
247 M Richardson (2006 Rd21)
245 J Bartel (2005 Rd16)
232 C Judd (2006 Rd5)
There's been a few retrospective scores released from before SC started:
267 N Buckley (2001 Rd13) - 37 disposals, 2 goals
262 M Lloyd (1999 Rd3) - 26 disposals, 13 goals
251 S Camporeale (2004 Rd2) - 32 disposals, 4 goals
243 N Buckley (1999 Rd16) - 43 disposals, 3 goals
236 W Carey (1999 QF) - 24 disposals, 6 goals
*can't remember where I got these from but they're on my computer lol