Hey Gary--we used to be able to buy a small spool of light gauge soft steel wire at the hardware store for wrapping joints. I have a partial spool left somewhere, but finding it is another question. For wrapping wire joints that need to be soldered, I get thick stranded copper antenna wire from Radio Shack, then just cut out single strands (for wrapping wire landing gear, etc.). One length will last a lifetime.

But here you're wrapping steel pushrod ends to a wood dowel. I presume there is a small 'L' bent into the dowel end of the steel rod, to fix into a hole drilled into the dowel, to keep it from sliding. Other than that, all you need is something to keep the steel end from falling off the dowel. I use nylon rod-wrapping thread. Carpet thread or button thread would also work. Start by wrapping the thread over its own loose end, wrap about an inch, and when you're ten turns from the end lay in a loop, wrap over the loop, then insert the loose end in the loop and pull so the tag end is buried under the last ten wraps. Then cut off the tag end and wet the whole wrap with CA to keep it from unraveling.

Or, go down to RCBW and get a Dave Brown fiberglass pushrod kit, which is maybe a little less work, holds up very well.