One of Cameron Douglas’ alleged meth suppliers will get his head examined after turning down a sweetheart plea deal.

Manhattan federal Judge Richard Berman yesterday ordered a mental-health evaluation of Eduardo Escalera after defense lawyer James Cohen said his client is “in denial.”

Last week, prosecutors agreed to drop drug charges and let the illegal Mexican alien plead guilty to illegal re-entry for a recommended sentence of 35 to 51 months. The order indefinitely postponed the pending trial of Escalera and his brother, David, who were busted last year after the son of actor Michael Douglas pleaded guilty to drug-dealing and agreed to cooperate with prosecutors.