back when .10 was first released i joined ladder and made my first ever sorceress.
after about 3 months of doing council runs one of them dropped a soj.
A tip you may want to know.
The game looks to see if you have a manald or nagerling.
If you have niether you have a 100% chance to get one of them before a soj.
So i suggest keeping all the unique ring you can.
Also another mf tip is to have your sorccer close to the required levelto use the soj ring.
which is level 29.