Hello Jon,
I found some interesting links and other info on the 503.

This link shows the jumps during WWII in a time line and includes the dates, place, unit, name of operation and mission:
http://www.specialforcesassociation....03.07.2013.pdf

Here is a Web Site about the 503. Be sure to click on THE STILL PHOTOS at the bottom of the page:
http://corregidor.org/heritage_battalion/index.htm

The book 'Three Winds of Death' 1st edition can only be found for big money. Thankfully they now have a affordable 2nd edition out. Below is a review of it followed by a link to purchase it.
Three Winds of Death - Book Review

Three Winds of Death


The photo of your Father.... Is there a chance you can post it?
Is there any view of a Unit Patch?

Artifacts of the 503rd

His service is greatly appreciated...

Regards,