Anal hooks are becoming more popular for both bondage and selfbondage sessions. You can invent many scenarios based on using such hooks (anally, vaginally or both). I resisted for a couple of years, but finally gave up and ordered one (see the places where you can buy anal hooks here).
As always I needed one urgently. But if I had more time and patience, I would definitely consider Skunsss’s design (Russian). Basically, it’s a kit. You can “construct” the hook or plug you currently need using steel hooks, handles, eggs, cones or balls of various sizes. There is even a teflon version (Yes, you can order all these things. Send a mail to scunsss-design on the server yandex dot ru for more info or ask on the LiveJournal page.)
The ring can be used not only for “suspension” but also for fixing/locking with crotch ropes, karada’s and other harnesses. Imagine, for example, a locked crotch chain threaded through the butt-plug ring. Absolutely inescapable without heavy metal tools.