I would use thick stainless TIG welding wire and fashion into shape. It bends fairly easily, to make circles you could wrap/tap with hammer around something the same size as you require. Once all the shapes are made you would then just tack weld together (TIG obviously) you would need a little plate made of stainless to mount ends. Plate with holes would screw to the underside of upper PF and somewhere to secure the bottom part of the ramp, to the top of an existing post or something similar. Polish up and would look a treat.
