Hi Jeff......many, many thousands of Webley Mark IV .380 (.38 S&W) revolvers were made and issued to British and other Commonwealth troops during WWII. I know of no way to trace a particular gun to a particular unit, much less, to any particular person.
Here's some general info on Webley revolvers: http://world.guns.ru/handguns/hg91-e.htm
As for approximate value, I can help you there. The Standard Catalog of Military Firearms lists the value at:
Exc. - $375
V.G. - $325
Good - $250
Of course, the pearl grips aren't original and will detract from the value somewhat.