It can be made with not much more than than an Oxy-acetylene torch, hacksaw, and drill press. The materials are probably all available at your local Big Box hardware store, though you should see if you could buy the angle iron as cutoff remnants from your local steel supplier, as it will be a lot cheaper.
Step 1: Materials and tools
Angle iron, approximately 2' x 2', 2 pieces 12-18" long
Angle iron, 3/4" x 3/4", about 2'
Steel flat stock, 1" x 1/8" thick, about a foot should be plenty
2" clevis pin and a cotter pin or clip
3/8 bolt, 1 1/2" long should do, or Metric 8, or whatever you find in your junk box around this size.
A nut to match your bolt if you don't have the right tap size
And the following tools:
Drill press and drill bits
Tap to match the threads on your bolt (optional)
Oxy-acetylene torch, and welding or brazing rod