I use earplugs made for sleeping (so have an emphasis on comfort over noise blockage) and that definitely helps.
I can't tell what brand I'm using because I (unhelpfully for this case) throw away the box and just keep them in the plastic bag they come in, but every 6 months or so I'll go to Fred Meyer, Target, or Walmart and buy a big pack of the most expensive earplugs that say "sleep" on the box :-)