One possibility would be used Paradigm Atoms. Not as good as the M3s but likely to be available for your budget. I got a great deal on a pair for $100 CDN, if you were up here I could sell 'em to you.

I would find a way to spend a bit less somewhere else and hold out for FO M3s ($270). It's easier to find decent cheap receivers than decent cheap speakers IMO.

Otherwise, just watch the dealers for clearouts.

M60ti, VP180, QS8, M2ti, EP500, PC-Plus 20-39
M5HP, M40ti, Sierra-1
LFR1100 active, ADA1500-4 and -8