I DIY'd one for my C64's 1702 monitor. I used a pine 2x12, clamped the corners with a 90 degree clamp and screwed them together. Counter-sunk the screws and filled with wood filler. I could have used my Kreg jig to totally hide them underneath, but, I was lazy that day. I then used gel stain to dress it up. Even the wife was impressed and allowed it to used in the house, LOL. Cost me a few bucks (before lumber prices skyrocketed) and about 45 minutes of time.