The best replacement for drysuit is wetsuit.

The best alternatives to drysuit are rated as following:
★★★★★  wetsuit
★★★  wetsuit diving
★★★  wetsuit surfing
★★★  wetsuit scuba
★★★  dry top pants
★★★  wetsuit kayaking
★★  semi dry
★★  wetsuit sailing
★★  wetsuit kiteboarding
★  wetsuit windsurfing
  immersion suit
  semi-dry
  wet suit

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

Other search terms related to drysuit and their ratings are:
★★★★★ bcd
You have in mind a companion for drysuit and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of drysuit in all years. Click on graph for more.
drysuit
wetsuit
wetsuit diving