A cheap vps is cheap and easy, and doesn’t require exposing your local network or making your friends install a VPN client. Old games don’t need much in terms of resources, but you may have trouble running them on a modern OS.

Note that because of that, you will be using software that almost certainly has known vulnerabilities. Take a backup or a snapshot in a known-good state that you can easily roll back to, and shut it down when you’re not using it, if possible.