Stop listing the names of sources. Don't name the address of the site or vendor. Never say their name, email or phone number publicly. Only pm trusted members the details.
There is no such thing about blocking non-trusted members. It's an illusion.
Look below here, most are blue posters.
https://sanctioned-suicide.net/threads/urgent-please-read-sn-news.53031/
Any pro-lifer or LE wanting to get the info will get it finger in the nose whether you post it in the open (including disguised with asterix or hints like "this jungle or art crafts site") or in PM. In other words, the more you share, the more you disservice no matter what your intentions. To achieve more efficiency, the best way would be to let the people down on their own do their homework and demonstrate their motivation by dedicating themselves to assembly the puzzle pieces without help, up to committing errors then more revised trials until success, since every info is out there, just sparse, but that doesn't seem the stance of this community, so be it. Consequently, tricking ourselves for comfort leads nowhere, but is really a flawed pathetic reasoning. There is no strict and ingenious solution applied. Even the PPeH lists SN and other sources that are plainly accessible.
I've known 18yo who were smart enough to put down any obstacles. So you bet that it's also child's play for anyone who has minimal investigation skills as a hobby and even more as a profession.
As long as a few members are capable to retrieve info to the point of sharing it, it means everyone else could have followed the same path. So if there is will to truly make a difference, then take yourself by the hand, stop asking for support and teach yourself to act autonomously in silence.
I've known members who turned down any assistance request with a fuck-off answer. Their choice. Fact is they were the closest to preserve the goal of the mainstream audience in the long-term.