There is one here for V4. You might be able to tweak the shoulders/collar for M3.

http://www.most-digital-creations.com/freestuff.htm

Sroll down a bit and it's on the left side: called "Future Prisoner.

Also, have you looked in the poses that come with Poser? Or the poses that come with M3?

"It is good to see ourselves as others see us. Try as we may, we are never
able to know ourselves fully as we are, especially the evil side of us.
This we can do only if we are not angry with our critics but will take in good
heart whatever they might have to say." - Ghandi