Call the spca. They will need to make you an appointment for an evaluation.
I suggest you call them so you can make sure they room for him. He has to be UTD on shots. Every stray I've brought in the SPCA has had an immediate opening. I paid a $10 shots fee and it's all good to go. A couple times I had to wait for them to open over the holidays or about a week for there to be space after a pet had been adopted.
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