Hi and thanks for your question!
It is possible to buy individual components from the set without a Raspberry Pi. Our cooperation with Turris is ongoing and currently two of our team members are looking into it.
In the past we have been shipping our software components via Docker but we might go away from this solution since we do not have support for it in Turris and we feel we may do a better job via native system packages.
So we are working on DEB packages and it will be possible to install them in Turris via LXC Debian container. Hopefully we will have Turris OpenWRT packages available as well one day
What is your opinion on that? Thanks!