If the "pink slip" is lost but registration current, can I sell a vehicle if the buyer has the registration, bill of sale, proof of purchase , and copy of the seller drivers license?

Duplicate pink slip from DMV, proof of reg, bill of sale (DMV one with odometer if newer) CA.DMV.org

In my own experience you can but if dmv ask the buyer for more information buyer will bring a form to sign every case is different but from the time I did it law change, wishing you the best