Derek, If you are going to make these, you need a repeatable match. I will come up with a match that works with this perfectly so there is no guess work. We'll go with a tapered match to make it easy to replicate. It will also scale better.
I got your drawings and updated them a bit. If you can cut me a sample or two for 5 turns, I will design a tapered match for you, build up one antenna and send it back to you ready to go with perfect SWR. I will also send you some tapered matching stub samples to build more of your own.
In addition, send me a couple of the antennas you have already made, I'll let you know how close you came to the mark, tune it for perfect SWR and send it back to you