The best replacement for hypochlorite is calcium hypochlorite.

The best alternatives to hypochlorite are rated as following:
★★★★★  calcium hypochlorite
★★★★  sodium hypochlorite
★★★★  chlorine
★★★  chlorine gas
★★  trichlor
★  chlorite
★  sodium dichloro s-triazinetrione
★  sodium dichloro
★  chlorine dioxide
★  dichlor
★  sodium dichloro-s-triazinetrione
  hypochlorous acid
  sodium chlorite

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

Other search terms related to hypochlorite and their ratings are:

★★★★★ ammonia
★★★★ sodium thiosulfate
★★★ sodium bisulfite
★★★ thiosulfate
You have in mind a companion for hypochlorite and it is not yet here? Propose!

Google Trends

Scale is based on the average worldwide traffic of hypochlorite in all years. Click on graph for more.
calcium hypochlorite
sodium hypochlorite