Build a North Creek Echo kit!
Canton makes some pretty good lower end... as well as higher end too... speakers. I bought a pair a year ago for about $200 and like them very much... for what they are. 87db 8ohms. Single pair of posts. Nice sounding.
Phase Tech doesn't get much notice IMO but they are very good speakers presenting a great value and sonics, for the money. I've two pairs of them.
If you're willing to go up to $200/pr, you could snag one of the last closeout pairs of Athena LS-300 towers (retail $500/pair) from Audio Advisor. I always liked the speakers from API: Good tonal balance, smooth, neutral, works well with all kinds of music. These floorstanders will also give you more of the bottom octave than most sub-$200 contenders.
At your target $150/pair, you'd be hard-pressed to beat the Energy C-200. 88dB sensitivity, bass into the low 40's/high 30's, handles up to 125 watts, excellent room-filling dispersion, good transparency and detail in a natural perspective, especially at that price.