Usually item properties and container/merchant inventories are set when you hit the alt key nearby or run your mouse over them. The exception is when an item is placed directly into your inventory.
IIRC there are only 2 potentially good rings consistently in the game, but I found a few randomly generated rings (dropped or for sale) that came pretty close in quality.
FYI, this is what I got, reloading probably more than I needed to;
Breastplate Of The Dragonheart
Durability 12
Charm Quality 3
Armour 440
2 Defense
100 Vitality
60 Magic
15 Resistance to Fire
40 Resistance to Lightning
15 Resistance to Spirit
4 Hearing
Survivors Instinct +1
Breastplate Of The Dragon - before the upgrade
Durability 30
Charm Quality 1
Armour 390
6 Strength
6 Intelligence
60 Vitality
100 Magic
15 Resistance to Lightning
15 Resistance to Poison
2 Hearing
Heaven's gift +1
Sapphire Ring - in Verdistis, from the patient healed at the start of game
Durability 10
Charm Quality 2
6 Constitution
40 Vitality
40 Magic
10 Resistance to Lightning
Alchemy +1
Ruby Ring - from the house north of the cursed Abby
Durability 10
Charm Quality 4
4 Strength
60 Vitality
40 Magic
