Sprinkler System Diagram How To Repair Damaged Sprinkler?

How to repair damaged sprinkler? - sprinkler system diagram

My nozzle is cracked. I think that Selena, but I'm not familiar with the parts of the sprinkler system. Where can I find the specifications or graphics on the Sprinker system? I have a 3 / 4 "Richdel DPR 711 (150 psi max).