A Nite Ize Gear Tie seems to do a decent job of supporting the MFJ-1820T 20 m whip antenna on my Elecraft KX3. I first tried forming it into a bipod, but then got the idea of attaching it to the SideKX endplates. Success!
I’m using a Nite Ize Gear Tie 12 inch because I had one. The fatter one didn’t really fit through the handles.
The whole setup is pretty cheap. $25 for the antenna and $6 for two gear ties. It isn’t as efficient as a 20 m dipole, but it is kind of cute.