getting trinity onto stretch

my little project thinkpad x200 now sports debian stretch and X; what it doesn't have is TDE. my line in /etc/apt/sources.list is: deb http://mirror.xcer.cz/trinity-sb /debian stretch deps-r14 main-r14 (and of course the deb-src line as well.) i've imported the gpg key apparently uneventfully. running apt-get update seems to do as it should, though it throws an "ign" for each of the trinity indices (i didn't follow it closely the first time i ran it, so this isn't necessarily unexpected). but sudo apt-get install tde-trinity renders an unable to find package error. aptitude likewise says it can't find tde-trinity. i'm clearly erring somewhere, but do not know where. how do i get the preliminary stable build onto the machine? thanks in advance. dep Sent with [ProtonMail](https://protonmail.com/) Secure Email. Because privacy matters.