I don't think the 1" x 1" are patches. They look like small metal plates mounted on a metal clip or slide via cap rivets. I have been playing about trying to replicate this clip and get the sizing on the rivets right. Just need to cut another square out then get it all assembled.
So after doing some measurements on one of the photos What we have kind of figured is that the top patch is 1"x2", maybe a name tag, and the other two are 1.5" patches, maybe pins. It also looks like in the corner of two there are rivets, but one of them can also be a medic patch. The other could be a platoon logo of some kind.
I'll draw up some basic designs in the coming days that can be used until we find the correct patches.
I think the smaller 2 are metal squares with small rivets in each corner. The bottom one has a larger rivet in the middle. I knocked up a prototype but having an issue cutting the squares to size at the minute.
I'm not sold on the rivet in the middle, but looking at them more we do think they are metal with etching in them. The top one looks velcro'd on, the bottom two may be riveted. That or the top one is a cross. The corners look fare more square than the bottom.
Hey! I was scrolling through pics of the NYCC and found this pic of Sappers bag. It's the first time I've seen an actual prop pic. Someone work some magic and see if you can get a clear shot of what's on the front of the bag.