Well, I finished surveying all the Mages Guilds throughout Tamriel. I have not verified and validated the data that was collected originally for Hammerfell, High Rock, and Skyrim. I do not know if I will do that either. It depends on how I want to spend my time.
So, based on the data that I collected, there are 2323 items available. Not everything is unique, and some of the Mages Guilds actually sell some of the items in pairs, which is a bit strange.
In case you are interested:
Bracelet: 503
Belt: 350
Torc: 285
Amulet: 271
Mark: 489
Crystal: 214
Bracers: 137
Ring: 74
Not all of the magical items combine with spells.
Mark: 31 / 31
Crystal: 29 / 31 (Missing: Free Action, Toxic Cloud)
Bracers: 29 / 31 (Missing: Free Action, Toxic Cloud)
Ring: 24 / 31 (Missing: Curse, Force Bolt, Fire Storm, Free Action, Wildfire, Purification, Toxic Cloud)
There seems to be a wide range of values for the same item and spell combination. For example, a Mark of Sanctuary ranges from 1250 to 1750, and there are 37 of them available.
The cheapest magical item with a spell, that is not made of Elven or Dwarven material, is 1250, while the most expensive is 39400, which is a Ring of Passwall.
If you are looking for defensive items, this is how the Ebony material items break down:
Bracelet: 19
Belt: 25
Torc: 26
Amulet: 21
If you are looking for attribute items, this is how they break down:
Strength: 88
Intelligence: 78
Willpower: 68
Agility: 80
Speed: 77
Endurance: 76
Personality: 80
Luck: 69
I will leave to the interested player to figure out which magical items are paired with these attributes.
Now that I have a complete set of data, I will see if I can confirm some of the values for the different spells, and determine the number of charges that the different magical items contain. I think that there is a mark that is worth 4200 for a very cheap spell, which means that it would exceed the assumed maximum value of 15 charges.
Depending on what I am doing this weekend, I should be able to get the new sets of tables created. If I cannot get the values for the charges to agree, then I will deal with them in a separate update.
Hopefully, for anyone that is using this data, you will find out where it will make sense to make your purchases for specific items.