Spear and Jackson Cordless Drill model SJ-CD18KUK

Worked fine for years, mechanically sound. Now after a short time of
use, there's a puff of smoke and it slows right down. Upon opening up,
I see this smoke is pouring from the centre of a 3-legged regulator
device on a heatsink.

I have looked here http://www.maplin.co.uk/Search.aspx?menuno=12489
but can't find anything with similar numbers. The markings are
NEC
K2 ??4
82M

The ?? are two numbers I can't see, as that's where the burnt hole is!

Unfortunately, I don't live somewhere I can just wander into a Maplin,
and Googling doesn't help, so any help appreciated. Thanks



The motor is a HongYang HRS-550S-18V