Each state in the Northeast has a directory of lenders for their C-PACE program. Connecticut is one of the most active states for C-PACE in the country so, they have several lenders listed. I would also suggest New York and Pennsylvania as good sources for C-PACE lenders. The C-PACE Alliance is trade organization of the lenders. https://www.c-pacealliance.com/about-cpa/members/
You may also want to look at the program administrator’s website. For example, EIC runs New York State PACE (outside NYC) and has a list on its website here. The providers have associated project types and financing ranges listed. This list consists of many of the big national PACE lenders. Slipstream has worked with most of them and views this list as quite robust.