Air Band - Dual Bander Antenna
Howdy
You might do a bit more research on suppliers and I would recommend looking at items such as Rocket Radio (UK) as an example, unless you are set on using a NMO, in either case drilling holes or overly expensive NMO mounts would be my last resort....
Others can chime in as suspect several have fit-for-purpose dual Air Band antenna installed.....
Also, as this is a 'receive-only' application the 'ground-plane' is always a 'debatable' subject, relative to improving receive levels, and I have use Marine Band Antenna(s) (fiberglass-no ground plane) in the VHF range with success as well....along with used Aircraft Antenna's as well...
Below is the URL for Rocket and perhaps a US supplier might be researched and found to have a like antenna...
Pilot Airband Scanner Mobile Minaret Antenna
Please let us know what you find and hope others will hope into the discussion...
Thx
Bill