I did some research on Clinton Locks when I found some original Clinton key blanks:
According to the National Register, The Clinton Lock Company was established in 1896 by David Batchelder. The Clinton key blanks and Clinton locks were manufactured in Clinton Iowa in the late 1800’s. I don’t think they were in business very long, because they only made one maybe 2 keyways Ilco CL1.
Here’s a couple of pics of the original blanks.

