Not hard to make your own "one off" gauge pod using a spare A pillar cover and some PVC or thin wall metal tube for the gauge mounts.
You then stretch thin stretch material over the unit to get the pleasing shape you want, and use resin to harden the material, then build a layer or two of chopped strand F'glass for some strength.....some sanding, filling and paint (or find a company that can vacuum cover with vinyl).
Its not a method that stands up well for mass production, but for a one time job, it works well. I made a formed rear parcel tray to cover some seat belt retractors on a car I restored....looked good.