TIL you can use Kermit – a protocol and software package from the 1980s – as an interesting SSH wrapper:

$ kermit -C 'ssh user@host'
$ kermit -Iis some-file.ext

It will send a special byte sequence that your local kermit will pick up on, and enter transfer mode. The file will be transferred, complete with integrity checking. Then you’ll be right back at your shell.

Relevant: Try the last Internet Kermit server.