Here’s a decent option for 57 GPM, hook it up to an atex motor and you’re good to go. A little expensive and probably need to replace a couple o rings, I prefer mag drive pumps because there’s no mechanical seal. As long as you’re running C1D2 though should work just fine. Also note the max rpm is 900 so you’ll likely need a VFD:
https://www.ebay.com/itm/334220005901?hash=item4dd110920d:g:HnkAAOSwZwFhknpp
I’d guess about $1800 all told with motor and drive, less if they accept an offer at $750