We had 8-10 get freeze damaged, so those were junk. We can usually get them going with the filter screen cleaning you mentioned. Only have them in a couple IBAs, so not blowing threw them by any means. If the filter cleaning doesn't work, we usually just replace and move on. There is a company selling 3d printed repair kits online also, I may try 1 or 2 out if I get time. Not a huge deal for us to replace, since we may do 1 or 2 in a year, and even that's a maybe. I'm not affiliated with this company and have never tried their stuff.
Works for Pro 324 Nozzle but fits many other similar models/sizes. They will work for any nozzle oriface size. This kit provides a 1 replacement black sleeve and 1 replacement bottom cap for the nozzle (*nozzle not included, color of parts may vary black or white but are all the same...
www.3dwashsolutions.com