Topic: Game Boy Pocket DMG-Design Price?

I have this beautiful Game Boy Pocket.
Never Used, and looks very nice.
I was wondering, if it's worth anything?
Unfortunately it's just the Game Boy, no box og manual.

Picture: http://tinypic.com/view.php?pic=351h400&s=5

$40

I'm not completely certain but I think it's a custom case.
I've never seen a Pocket with original Game Boy pink buttons. Plus the fact the D-pad doesn't fit snugly in the slot also suggests its fanmade.

It isn't a Custom
It is a semi-rare Japan only, first edition of the Game Boy Pocket.