I once worked on a handheld garmin gps that used a 386 ... not sure if it ever became a product, though.
It definitely had moving map... 1MB of it.
I think it was one of their first models that had a map, earlier ones would just display coordinates/tracks/waypoints.
Edit: here's a teardown of an older model where you can see the CPU: https://www.eevblog.com/forum/repair/garmin-gps-12map/, and the wiki for the CPU has a clearer picture: https://en.wikipedia.org/wiki/Intel_80386EX