I bought a set of wet sanding blocks from these guys a couple years ago before they started selling full blocks sets. The do the best bodywork I've ever seen, and they use and promote acrylic/plexiglass blocks. After trying them on clear I started making my own from leftover pieces we already had at the shop. Definitely check out the "learn" tab on their site, its full of really great info on bodywork.
https://www.trueblox.com/
Check out pics of their work on Instagram.
https://www.instagram.com/p/Bzt73XRg...ns_share_sheet
https://www.instagram.com/p/B0pF1Nag..._web_copy_link
https://www.instagram.com/p/B4D6Dbwg..._web_copy_link