Yes, it's possible to change any of those LEDs, but that doesn't mean they'll be standard or even easy to replace. Some of them may be surface mounted. Is it worth possibly damaging your CD-ROM, etc.
Sony has taken the wraps off a new backlight tech for LCD panels known as RGB LED. In really simple terms, it's similar to existing mini-LED backlight tech, such as that offered by the BenQ MOBIUZ ...