For anyone who’s interested, look up the following items on Amazon. (Can’t post links here)

• SmallRig 5.5” Magic Arm - $18.99
• CAMVATE Crab Clamp - $12.80
• 5/8-inch male to 1/4-inch female mic screw adapter - $5.99
• PanaVise 312 - $21.89
• PanaVise 305 (or 300 if you prefer a little taller.) - $24.49

Just under $85, but it’s much better than the PanaVise 350, in that you can position the lock any way you want.

I’m pretty pleased with how it turned out.

EDIT: Added Amazon (non-affiliate) links if anyone wants to build one of these. I would recommend sticking with the named brand, especially the SmallRig… I’ve tried knock-offs that are VASTLY inferior. The SmallRig MagicArm is really solid.

NOTE: The hole in the PanaVise base is not threaded, but it is exactly 5/8”. If you loosen the vise, put the 5/8” adapter in and tighten it, it will stay solid. Then you can screw in the MagicArm to the adapter. If you’re worried about damaging the threads, I suppose you could put some tape around the adapter, but I didn’t bother.