mechanicalMechanical spots seem to give a lot more mining probes than research. I am also wondering how to obtain more research probes.
I don't remember seeing any as random mission rewards, altho ialthough I did get a few from afinityaffinity and main story missions.
Currently iI have mining probes coming out of my ears xD (25+ unused and iI mine more than my storage can support xD). Very few research and storage thothough (100k ish revenue from research, 21k storage).