Alternate for Raspberry pi 3

Hi we are making an ROV with 8 thruster configuration. We are looking for an alternative for companion computer ( Alternate for Raspberry pi 3 ). Because the availability of the Raspberry pi 3 is very less.
Is there any alternate for the companion computer?



BlueOS is currently able to run on Raspberry Pi 3B/3B+/4B. It is designed to be reasonably self-contained, which should make it possible to run on other linux-based single-board computers if that’s something you’re interested in.