Each of the weapons has 3 materials that are used to paint on in the game's paintshop. Each of these materials is assigned to a mesh that is basically a copy and paste of the meshes that make up both sides and the top where they can be painted, so in those spots verts are basically doubled. I just selected the objects with those materials and deleted. I didn't bother reducing anything else to keep it as high detail as possible, except a few materials if they used the same images.
Although i just opened the svg from the beta and it doesn't seem to have those materials, so next best option is to download a newer version of maya and reduce there.