Port forwarding multiple webservers, DG1670A/TW

I currently have one webserver with django/nginx connected to my Arris router DG1670A/TW (loaned by Spectrum IP provider). Perhaps the following info is superfluous for answering my question but here are the configurations anyway, for my current website:

-‘firewall->port triggers’:
–‘outbound port’ 80-80 and ‘inbound port’ 80-80
–‘outbound port’ 443-443 and ‘inbound port’ 443-443

-‘firewall->virtual servers / port forwarding’:
–‘outbound port’ 80-80 and ‘inbound port’ 80-80
–‘outbound port’ 443-443 and ‘inbound port’ 443-443

Ports 80 and 443 are used for the current website. What is your opinion, advice, answer or alternative solution for 2 servers on one public facing IP: Can I use a 2nd physical server for a 2nd website (different domain name)? It seems to me that default http and https require those ports and setting up a second website would require a user to tediously type ‘www.2ndwebsite.com:8080’ while nginx is configured for listening on port 8080. Perhaps I just need some new hardware to make this work, like a switch?