My wife saw this costume a couple years ago and we thought it was great.  We have triplet twelve year old boys and they like to dress in group costumes.  We gathered up old long sleeve shirts, cargo-type pants, belts and boots from around the house and local thrift stores.  We used a spray paint primer on everything first.

We then began putting multiple coats of green paint on everything!  The more you paint the clothing the shinier it gets.  We used over 40 cans in this entire process!  Making the gear was the fun part.  The mine sweeper is a Frisbee mounted on a broom stick.  We also used the cord from an old keyboard and a cardboard box to make the mine sweeper look realistic.  We had an old pair of binoculars and a non-working walkie talkie at the house.  We just spray painted those items.

The helmets were purchased at a dollar store and were also primed and spray painted.  We had to purchase the face masks because we thought they looked much cooler than just using makeup.  They are called a morph mask or an invisible man mask and can be found at any Halloween store.  The flag was cut out of cardboard, spray painted and duct taped to another broom stick.  The bases were made simply by cutting the shapes out of cardboard and putting a few layers of spray paint on them.

The boys love the costumes and the reactions they have been getting are awesome!  If you are looking at doing something similar to this I would recommend starting well in advance of the date you plan to use them.  We painted everything over a period of about seven days, allowing everything to dry before adding the next coat.  There are a lot of hours that went into the creation of these costumes but the result was well worth the effort!!