cali41, I believe they're known as "vine supports." Nowadays they seem to be clear plastic instead of metal (wouldn't need to be painted). Note that the first of these ads is from Ace Hardware: maybe they were confused by the change in design and materials.
http://www.acehardwareoutlet.com/ProductDetails.aspx?SKU=73292
http://www.starnursery.com/landscape-supplies/tree-ties-stakes/sturdy-vine-supports-16-pk.html

I've also read of people using "vine eyes" (a type of screw eye). Here's a project for making an elaborate wire grid which is attached to screw eyes or hooks:
http://www.bhg.com/home-improvement/outdoor/pergola-arbor-trellis/lacing-a-wall-trellis/

Are they perhaps from Lee Valley's wall trellis kit?

Here is a link that might be useful: wall trellis