Here are some quotations using this word, taken from

Meanwhile, a poor copy was erected in the courtyard; many an unsuspecting traveler paid homage to that ersatz masterpiece.
--Edith Pearlman, "Girl and Marble Boy," The Atlantic , December 29, 1999

All we can create in that way is an ersatz culture, the synthetic product of those factories we call variously universities, colleges or museums.
--Sir Herbert Read, The Philosophy of Modern Art

Then there was the sheaf of hostile letters larded with ersatz sympathy, strained sarcasm or pure spite.
--"Time for GAA to become a persuader," Irish Times , Monday, April 13, 1998