It's a veritable slice of urine to make your own if you don't like what's on offer, you know. If you don't have the skills or tools yourself, you probably know somebody who does. The boards are out there; some cheap, some... not so much. The 510s too. There's nothing about the box that requires it be made of cast zinc. Stabilized wood? Delrin? SLA alumide? Sheet metal? Go for it. Do it right, and it'll outlast anything you can buy off the shelf.