The best replacement for proac is harbeth.

The best alternatives to proac are rated as following:
★★★★★  harbeth
★★★★  pmc
★★★★  dynaudio
★★★  spendor
★★  monitor audio
★★  tannoy
★★  sonus faber
★★  vienna acoustics
★  totem

Your alternative for proac is not listed? Suggest!
Speaking about proac, one probably shouldn't forget about naim.

Other search terms related to proac and their ratings are:
★★★★★ naim
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