200 bhp K series

[DKL]

My caterham runs the 1.6 ss engine so around 140bhp.
I'd like a bit more but just changing the car isn't really an option. I imagined I'd buy a vhpd/r400/elise190 engine and drop that in but they are remarkably hard to find it seems. Looking at the exige website it seems they are very sought after now.
DVA offers a K06 kit which runs to 175 bhp based on mine for about £4k which is alot to not achieve what I want.
Alternatively a 160 vvc engine from a dead MG, jenveys, emerald ecu and I'd be getting close ish I'd imagine.
Anyone suggest a better option short of a duratec.
Thanks

[DKL]

Thanks both.
I have the 6 spd box and an open 3.92 diff.
I can't sell as there are only 4 vhpd 21s one of which is now a duratec.

The £5k sounds about right, just got to decide if it's worth it!