If you feel like you need a spring at the base, you can add this:
https://www.theantennafarm.com/catalog/larsen-spring-3877
But you may not need it. The Larsen whips are pretty flexible.
I've got a 27MHz version of that antenna, and I've owned it for going on 30 years now. It's been through a lot of parking garages on the roof of full size trucks, it has hit a lot of low tree branches. Still going strong after all these years.
Mounting an antenna horizontally when everyone else is using vertical polarization is going to greatly reduce performance.
The only "low profile" low band antennas I've ever seen were the rail antennas that were long metal structures designed for the roof tops of locomotives. They looked like this, but were MUCH longer:
Sinclair - Railroad Train - 159.50-163.50 Transit Antenna No Cable/ Connector (ST221SF1SUFF1610) from Solid Signal <— that's a VHF high band railroad antenna, the ones I recall for low band were 4-5 feet long.
Other option was diplexers that went in line with the AM/FM antenna, but that won't be an option on the new Canyon/Colorados due to the low profile antennas on the roof.
I imagine if you really wanted to get creative you could due a tape antenna on the window, but you'll likely have issues with the window tinting, plus it'll pump a lot of RF into the cabin. Not something you want to do.
Really, the base loaded whip is going to be your best shot if you want anything resembling performance and will flex as you go through the garage.