I know you're trying to avoid making one yourself, but if you do, a simple solution is to find a piece of generic tupperware or planter box that's the right size, & use it as a mold
for the glass & resin option. So, poof, a custom pod. Then just add a face plate for it to bolt the instruments to.
And a piece of flat aluminum
attached to the traveler track's bolts on it's underside can be bent to whatever angle you desire, to attach the custom pod to. Or use a piece of flat stock to bend into a custom bracket for mounting around a rail.
An option that's a bit more work, is to glass the pod to the deck
at whatever angle you choose, so that the faces of the instruments are at the ideal angle for viewing. This used to be a common solution on racer's, especially those with dual helms & helming compasses. So that the helmsman had the necessary readouts right in front of him, kind of like a Heads Up Display. And the same was done for the trimmers.
Old idea, I know, but in the 70's & 80's just having instruments was fairly revolutionary. And... it worked. Still does.
Halved or quartered PVC pipe is good for laying up glass corner sections in. And they then get attached to pieces of glassed 3mm ply/frp sheet in order to form small boxes & structures.
Just try & do all of your glass fabrication at once, as it saves a lot of time overall. Given that setup, making jigs, etc. is a big chunk of the time that goes into fab'. And making some extra parts
, or sub-assemblies often pays off later when you decide to either add more instruments,, or alter your current