Well, the Polo pocket does fit, but not perfectly...

It is a very little bit too tall at the front - it's
slightly wedge shaped, causing the top and bottom of the
frame to bow slightly down and up respectively.

Slight pressure straightens it out, so I mounted a post,
made from a PCB mounting post, front/center, to spread the
top and bottom back to their normal distance. It does halve
the width of things you can put in the pocket, but provides
a handy handle for removal of the pocket. The top of the
pocket is perforated with holes large enough for fingers
(ventilation?) but the metal edges of the sleeve are pretty
sharp, and it's easy to scrape or cut your fingers trying to
remove the pocket that way... it is a pretty tight fit.

The post looks a little odd, but I won't be seeing
it much anyway...