Si2x products:
http://www.six-2.com/Products/type_1
This is the product that resembles the distro in your photo on the first post...
http://www.six-2.com/Products/detail.aspx?productid=16
Look on the left of the screen and click on "floorboxes" these are the simple 4 breaker style boxes that sit on the floor. Like most Distro companies, you can always call them and ask them to customize the distro for you. For example; you could have them remove the L14-30 plugs from each end of the box (the link above) and just have them install a pigtail on one end for you with a plug of your choice... They also carry adapters, cables, and just about any other power or speaker cable you need.
Here's what the floor boxes look like...
