If you're paying for a seedbox you can either get a vps (Linux VM) and do it yourself or just pay for the rutorrent web interface. I use to use dediseedbox.com awhile ago and had no complaints. My suggestion is to just have whatever provider host it so you don't have to use docker or anything.
If you want to do it yourself, then docker is the way to go and you should probably get a VPN on top of that so your traffic is mixed with other people. A dedicated server or VPS means you get your own IP and it can be linked to you.