Yes, you can file RTI to Slum Rehabilitation Authority, Mumbai.
Slum Rehabilitation Authority (SRA), was established as per the provision 3A (1) of Chapter I-A of Maharashtra Slum Areas (Improvement, Clearance and Redevelopment) Act, 1971 State Government of Maharashtra vide Housing and Special assistance Department notification no. SRP/1095/CR37/Housing Cell, dated 16 December 1995. SRA is a "Public Authority" under Section 2 (h) of the RTI Act 2005.
You can file RTI to SRA by addressing the same to the designated "Public Information Officer (PIO)" by paying the prescribed fee.
To know more about the procedure to file RTI Applications in the State of Maharashtra, please refer https://onlinerti.com/how-to-file-rti-online-for-maharashtra