A friend asked me if I could recommend a cheapo, light external antenna for his handheld, so I came up with this instead. It's relatively cheap, can be built with hardware store materials, and should be much better than the rubber ducky antennas that come with handheld radios. You should be able to mount it with cable ties on a 25mm pipe, or broom handle, or whatever you have at hand.

I designed the 3D printed body, the lid, the choke coil tube and the end plugs myself in FreeCAD, used Gembird PETG filament to print, printer is a modified Creality Ender 3 Pro. Elements are 6x1mm pure aluminium pipes, cable is RG-174, connector is SMA female for HTs. I used SDRAngel's "Antenna Tools" module for element length calculations (70cm: elements 163mm, total length 327mm, 2m: elements 491mm, total length 982mm) and stole the choke idea from a very nice tutorial (link at the end). Elements on one side are connected, and the feed cable is connected to the 2m elements. Connections are made with crimped on 3.2mm ring terminals, and I used appropriately sized blind rivets to fix them to the elements. I filled the inside of the case with hot glue to fix and weatherproof everything, and put a lid on with super glue, plus shrink tubes on the elements. I made cutouts for cable ties for mounting the choke and the antenna itself, and the round part at the back is for a 25mm diameter pipe or whatever you have.

You can also use RG58 cable with a more robust connector, but you either have to modify the 3D file, or carefully drill out the hole for the cable at the back. I'll include the choke tube for RG58 too.

This is where I took the choke idea from: https://www.youtube.com/watch?v=N-rUeIMYXbg