how about £25, but not quite covert
http://www.the-outdoor.co.uk/include...53&start=0&sea
rch_string=body+armour&search=Search&price_range=

Going by the description there, it says something about "no filler" -
could this be the armour that's missing ?

For £50, it looks like you can get ex-police body armour, not sure
what the stab level is though...

http://www.britishmilitarysurplus.co...hopscr118.html