Yep, it is the internals from a flap control. Basically a screw jack with a 1605 ball screw and I think a double nut, roller bearing at the top, then two thrust rollers and a roller bearing at the bottom.
It came from a scrap metal metal chap, who deals in ex-MOD stuff ....... I think it was a fiver!
I ground off the beautiful 90deg. helical gear that was on the shaft and fitted a bored timing pulley. Shame, but I didn't want to have to sort out the end float on the drive shaft.
Fourtunaley, the screw is about 1/2" longer than the quill travel!

I am going to buy a piece of steel for the quill plate.

Cheers

Mark