There are tons of good places to go for Neuro/SCI. I went to TIRR Memorial Hermann in Houston. Several of my colleagues went to the Rehab Institute of Chicago, The Rehabilitation Institute of St. Louis, or Froedtert Hospital (Milwaukee). All of them reported great experiences particularly in terms of SCI and neuro populations.
In terms of mental health, I went to Mendota Mental Health Institute in Madison, WI and I LOVED my experience there. I was able to see the continuum of care in mental health services. As an added plus, they often provide free room and board to level 2 students.
Just a word of caution. Your fieldwork coordinator is required to set up contracts with wherever you go on fieldwork. Most students go to places with pre-established contracts. Often fieldwork coordinators do not like to create new contracts, particularly if the facility is only going to take one student over the course of several years. Just make sure you are in good communication with your fieldwork coordinator before you get your hope up.
There are a lot of options for neuro in the Philadelphia and surrounding areas. Here are a few options:
Good Shepherd Rehab Hospital-main campus is in Allentown, PA with outpatient sites in a variety of areas; Moss Rehab, McGee Rehab, Thomas Jefferson Hospital, University of Penn( Good Shepherd Penn Partners does the rehab). Not sure about mental health. Good luck