A big mapping url schemes to their protocols' default ports. See comments below for notes. Painstakingly assembled by crossreferencing https://www.iana.org/assignments/uri-schemes/uri-schemes.xhtml and https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml

scheme_port_map.json

{
  "acap": 674, 
  "afp": 548, 
  "dict": 2628, 
  "dns": 53, 
  "file": null, 
  "ftp": 21, 
  "git": 9418, 
  "gopher": 70, 
  "http": 80, 
  "https": 443, 
  "imap": 143, 
  "ipp": 631, 
  "ipps": 631, 
  "irc": 194, 
  "ircs": 6697, 
  "ldap": 389, 
  "ldaps": 636, 
  "mms": 1755, 
  "msrp": 2855, 
  "msrps": null, 
  "mtqp": 1038, 
  "nfs": 111, 
  "nntp": 119, 
  "nntps": 563, 
  "pop": 110, 
  "prospero": 1525, 
  "redis": 6379, 
  "rsync": 873, 
  "rtsp": 554, 
  "rtsps": 322, 
  "rtspu": 5005, 
  "sftp": 22, 
  "smb": 445, 
  "snmp": 161, 
  "ssh": 22, 
  "steam": null, 
  "svn": 3690, 
  "telnet": 23, 
  "ventrilo": 3784, 
  "vnc": 5900, 
  "wais": 210, 
  "ws": 80, 
  "wss": 443, 
  "xmpp": null
}

schemes_without_netloc.json

[
  "mailto", 
  "about", 
  "sip", 
  "tel", 
  "data", 
  "urn", 
  "bitcoin", 
  "pkcs11", 
  "magnet", 
  "blob", 
  "sips", 
  "news", 
  "geo"
]

Yes, you're probably right re. being non copyrightable. I think your comment here should be enough in case anyone has concerns. Thanks :)