Per l'oggetto della visione del vero, ho trovato questo:
True Seeing
Why you need it: Illusions tend to be "no save, you just don't know what's going on" effects. Also, miss chances can make you pull your hair out if you rely on attack rolls. True Seeing is the hard counter.
Cheap:
Scout's Headband (MIC). 3400GP, head slot. Allows you to flush out all of the item's daily charges to gain True Seeing for one minute. Standard action activation. Can spend fewer charges to gain lesser vision-based benefits.
Eyes of Truth (MIC). 5500GP, face slot. Once per day, True Seeing for one round. Swift action activation.
Standard:
Runestaff of Divination or Vision (MIC). 21000GP or 16000GP, respectively, held. As runestaffs, these are only useful for those who have arcane spell slots, but if you're a Sorcerer or such, they will do just fine.
Chalice of True Seeing (DComp). 21600GP, held. Standard action activation, True Seeing once per day.
Truelight Lantern (MIC). 36000GP, held. Standard action activation, and only 10 minutes per day, which looks limited for the price, but is rather unique in working within a radius rather than just showing everything to you, which means your party gains its benefits as well.
Rod of Revealing (DComp). 60000GP, held. Not real True Seeing, but the rod creates an effective antimagic field for 110 min/day that suppresses illusion spells only. Specialized, but makes Illusionists cry.
Deluxe:
Hathran Mask of True Seeing (UE). 75000GP, face slot. Continuous True Seeing, off you go. Occupies the face slot.
Gem of Seeing. 75000GP, held? Offers True Seeing for up to 30 minutes per day, divided up as you wish. The reason this isn't completely inferior to the Hathran Mask is that this one doesn't explicitly take up a body slot. Try Sovereign Glue-ing it to your eyeball.
Not recommended:
Helm of Vision (DotF), Continuous custom item of True Seeing (DMG), Eyes of the Spider (CotSQ).