Not that it matters for the question, but a V-Rex is a short wheelbase and a V-3 is a long wheelbase.
Honestly your best bet for a new seat mesh is to take the old one off and use it as a pattern to have a new one made locally to you. Anyone with a sewing machine should be able to do it. The best material to use is polyethylene screen material. The stuff is incredibly strong and will last longer than you do. Reflective material is optional.