The hard drive in my 760 was a Seagate 250GB IDE. You can use any other IDE HDD, up to 250GB. Make sure the jumper is set to MASTER, install in the 760.
When you'll turn on the recorder, you'll get an error message code that looks like this "0X00054...), disregard it, erase the HDD using the functions and that will format the HDD and you're ready to go.
I flashed my 760 with this firmware available here, http://www.twowheels.force9.co.uk/liteon.htmThis firmware allows you to put a larger HDD, up to 500GB, in the 760. I installed a Seagate Barracuda 500GB SATA HDD in mine using a SATA to IDE adapter available on eBay for about $5 free shipping. Been using it for over a year know and it still works great.