I had a friend 3D print an AFM pipe without the AFM in it for when I tuned the car on the Link ecu. Keeps the intake set up looking factory and means you don't have the AFM sitting in the intake doing nothing and looking messy.
There’s a whole thread on legacygt.com where people have made random 3D printed bits.
I imagine if you can get gauge holders sorted for the vents and centre cubby for the 4th gen Legacy’s you’ll make a few bucks for sure.
The only other guy I know of making them 3D printed style currently is pretty rough so if you could improve on that there is a heap of potential. He’s gone with a modular approach where you clip more pods on which doesn't look all that tidy
Upholsterer?? Can't say I've ever considered sourcing some from an upholsterer.
I just buy 10+ of every style my car needs from partsouq at next to nothing and slowly burn through them as they get wrecked upon removal.