Looks like I've got BSD SSH installed. From `man ssh`:
-o option
Can be used to give options in the format used in the configura‐
tion file. This is useful for specifying options for which there
is no separate command-line flag. For full details of the op‐
tions listed below, and their possible values, see ssh_config(5).
`Port` is on the list underneath. So I think the idea is you run
ssh -o <option_name> <option_value>
where the first can be `--port`. This looks like it will be really handy for me for the exact reason GP said.