Assuming that you mean this bolt:
I recently made one of those. They are a 3/8 bolt threaded 18 threads per inch, which is not a commonly available thread size. I purchased a 3/8 shoulder bolt, but off the threads, rethreaded the shoulder with a die I bought for the purpose, then ground the head until it was round and cut a slot. It needs to be blued but other than that I was quite pleased. My plan is to make more but it won't be done til I have time in all the other projects and commitments.
I have seen parts diagrams with numbers but can't for the life of me find them now in all the folders on my computer so can't give you a part number. However, it wasn't that hard to make and it will look original when done instead of cobbled together.
