Here's how I like to make them using 1/8 x 1 inch mild steel from Lowes. My plan was 8/32 bolt hole center drilled in plate 4 1/4 long and .90 high to match all my Soddy Daisy guns.
Drill the bolt hole first with a #16 drill. It's much easier than trying to drill a precise hole in a finished plate.
Make your measurements from the bolt hole and use painters tape to make precise cut lines for the straight lines.
Put the lock bolt in the hole and draw around the head with a sharpie and then fill in the area of what you want the final part to look like.
Carefully hacksaw and file away the excess material checking your work for symmetry. I did this one in just over an hour without hurrying.
