The panel itself is TTL, I have no idea what the existing controller is without a data sheet so unless you can find a data sheet for the existing controller it's probably best just to replace it with something else. What you need a 24x2 bit 1024x768 5 volt TTL controller (sometimes called 24 bit double pixel, 48 bit, 8bit 2 port). I work with these panels all the time retrofitting old industrial controls. What sucks is the terminology for TTL LCD signal exchange isn't very standardized. Making the cable to connect this all together is a PIA but it can be done.
They call it 8 bit on the data sheet you linked to, but that's 8 bits for each of the 3 primary colors 3x8=24. On top of that it's 2 wires (A and B) for each bit making 48 wires just for the color data, plus connections for ground, power, data enable, dot clock, then the backlight inverter power and inverter control signal.
Try to keep the cable length from the controller to the panel as short as possible. If the cable gets to be more than a few inches long it helps to use shielded cable for the dot clock. I wouldn't go much more than 10-12 inches total cable length. The inverter cable length isn't that critical.
This controller specifically the ARV-1575 will probably work. 5 volt TTL is what you have. The specs on this controller say it will work with an NEC_NL10276BC30-15 which most likely has the exact same pinout but might be a different version with a different coating on the screen or different backlight. They may even have a cable available. It seems the ARV-1573 is only VGA input, you may be able to find one with a DVI input, just look for 5 volt, TTL, 24x2 bit. Some motherboards also have TTL capability.
If you get the data sheet for the controller, email it to me and I can tell you if it will work and how to hook it up- turbochris at krugtech dot com
Have you figured out the touchscreen hookup?