MSPs (managed service provider, basically outsourced IT) are a great source of leads, and they often have customers in widely different sectors. They seem to get a constant trickle of software development work. Maybe one out of ten of these could turn into something big. MSPs will want 33%-50% of total for finding the lead so be up front about how long you pay them that finders fee (first $X thousand). Eventually that small project could turn into something full time. So pre-covid, you could go to Spiceworks (or similar) meetups, not sure best way to reach out to them now.