Patrick, I can tell you how to make them. If my camera had not just eaten itself I could post pictures. I used threaded galvanized pipe and all dimensions are ID. You may have to fiddle with the length to fit your preferences.
The handle is one 5.5"x 1.25" threaded pipe. (1.25" ID gives you 1.5 OD)
One 1.25" to 1" 90 degree reducing elbow
The vertical peice is one 6"x1" threaded pipe. (you can go longer or shorter depending on how it all fits together for you)
One 1" to 3/4" 90 degree reducing elbow
The part that holds the fitness weights is one 6"x3/4" threaded pipe. You put the weights on this. 3/4" pipe perfectly holds the 1" hole of fitness weights. Then put a pipe cap on the end of this. I use big washers to space it better.
It is better with a photo. But what you have is your handle across the top reduced to the vertical piece reduced to the piece that holds the weight. One side is open. The weights will be parallel to your handle.
I have my largest one built up to hold #58 and it feels very sturdy. It is not the same feel as a KB, but it is way cheaper and more adjustable.
Let me know if this helps.