[Ardupilot]Cheap Pi HAT

Hi All,

I have several Pi devices ( Pi zero, Pi 4,… etc) on my shelves since I use them a lot in many projects.

I found several posts that use Ardupilot on Pi and I am willing to do the same. I would like to use a Pi as my main flight controller.

I wonder if there is cheap Pi HAT that I can order from internet and directly use it ?

OBAL is good but will require time to get the PCB and solder the components on it.

I know about NAVIO2 but it is very expensive. I am looking for cheaper options.