This recipe is for installing FreeBSD 10.3 amd64 version in your AWS VPC. From this instance you will be able to accept incoming connections directly to your public IPv6 address, as well as making outgoing connections to other public IPv6 nodes. The processor, memory and storage requirements for this easily qualify for the AWS free tier.
You can also deploy a dual stack host-based firewall for FreeBSD using pf. This will be covered in a separate writeup.