Just thought I would upload some firmware for you Liggy, this is a strange one the drive shows up as a 7740H but existing firmwares are con compatible citing that the drive range is different.
I don't know what to make of it but the drive seems to be different 
Anyway it was manufactured in 2012 so it's not exactly new but this certainly appears to be a revision of the existing model or a comletely new drive with the same name.
Bought as a cheapie replacement for the mrs. laptop
Firmware: A842.bin