It typically runs on a Mstar MSD3663LSA processor with a 25Q64 SPI Flash chip.
DEXP, Telefunken, Supra, Harper, Hyundai, and Yasin.
A goldmine for service manuals and flash dumps for this exact chassis.
Chassis TP.MS3663T.PB751
Because this specific "IRIS Backup rar" is likely a technician's dump from a working unit, you'll find it on specialized repair forums. Here are the most reliable spots to check:
Provides specific downloads for 1366x768 models.