A CRJ-200 First Officer reported high oil temperature on their left engine. They ran the QRH procedure and diverted to the nearest suitable airport; unfortunately receiving little assistance from the company; despite multiple requests for same.

Narrative

[When] we received the aircraft the [previous] crew said they experienced a left engine low oil pressure en route. Maintenance serviced the aircraft and corrected the issue. After two engine run-ups; it checked good. On climb out at approximately 14;000' MSL; the Captain and I noticed the left engine oil temperature rising into the caution range. The Captain transferred the radios to me and he performed the QRH for high engine oil temperature. The engine oil temperature peaked at 165. We reduced the left engine thrust to approximately 60% N1 to maintain the engine oil temperature in the normal range at 149. QRH checklist was complete. I transferred the radios back to the Captain. We continued climb to FL190 and made it our final altitude. Maximum N1 on the left engine level at FL190 was still 60% to contain the oil temperature. During this time; we sent 3 ACARS messages to the company advising of the situation. We received no response. The Captain transferred the radios to me and he contacted the company through Commercial Radio. The Maintenance Controller's response to the Captain was 'I don't know what to tell you'. We decided to divert and chose a nearby airport. The Captain notified the Maintenance Controller that we are diverting. We were approximately 75 NM west of the airport at this time. I notified ATC while the Captain notified the Flight Attendant; the passengers; and our divert airport's Operations. We landed at our divert airport without further incident.