Minor Modification to the Goggles of the Golden Sun [3.5]

[Temotei]

The goggles of the golden sun (MIC, p. 205) give immunity to blindness and dazzling effects and the ability to sacrifice a prepared spell or spell slot of 3rd level or higher to cast fireball, but the DC is set to 14. The goggles normally cost 4,000 gp. How much would you increase the cost to allow the caster's normal DC for 3rd-level spells work with the fireballs from the goggles?

[ExLibrisMortis]

A staff of fireball (if there was such a thing) would cost 375 * 3 * 8 = 9000 gp. That gets you fifty castings of fireball using the wielder's save DC and caster level.

A runestaff of fireball* (again, if there were such a thing) would cost 400 * 3 * 3 + 100 * 3 * 3 = 4500 gp. That gets you three castings of fireball per day, using the wielder's save DC, caster level, and spell slots.

Given that the goggles are usable three times a day, and use your spell slots, I think they closely match a runestaff with one spell, which would cost 3600 gp. If you call the immunity half the price (2000 gp), you only need to add 1600 gp to the price to reach the equivalent of that runestaff.



*Plus some other random third-level spell usable 1/day. Runestaves are suggested/required to have two to five spells, not just one, and no spells lower than third level.