Hi guys, welcome to the UACM section.
I am the squad leader of the United Americas Colonial Marines. We represent the vast majority of Canadian Colonial Marines, however, not all consider themselves UACM... not for the matter of not getting along, simply because a few choose to be "screen accurate" and keep USCM patches and tapes on their uniform.
Our adopted flag is the United Americas flag... this flag was designed by Ron Cobb, the conceptual designer for Aliens. The United Americas flag was originally supposed to be on the Colonial Marine's uniform on the film, but for a reason I am not quite sure of, the US flag made its way instead. Here is his original sketch:
The maple leaf is only represented on our ship's patch, the UAS Macdonald. You can find the artwork for our patches here:
http://www.pbase.com/sharpuscm/uacm
For a lack of better words, the UACM patches are sold out. I had originally 50 sets of each, but now they are all gone. I will in the near future get more sets, but I will need enough interest to run another purchase. You have no obligation to wear UACM patches when I do get them produced, but its nice to have more Canadian on board with the program, much like our UKCM members do with their patches.
In the interim, if you are looking for USCM patches, eBay is a good start... we also have members running screen-accurate patches on our PX section (you will be granted access eventually). The eBay patches are close to what they should resemble, however, some people here may find them to be crude copies.
As for uniforms (it's in your topic, so I'm covering it), there is no longer a source for screen-accurate combats, but the approved UACM alternative is a MultiCam uniform with the mandarin collar jacket.