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The Blindsight spell, from Magic of Faerun, quite ironically, gives you blindsight. I don't know of any premade magic items that give blindsight, but making one wouldn't be difficult at all.
Is True Seeing close enough? It's a 5th level Cleric or 6th level Wizard spell in the PHB. It's not EXACTLY the same, but a lot of the abilities overlap.
Its a feat in MoTW, iirc, with the [Wild] descriptor a small radius, and blindfight as a prereq radius. Also, Ninjas of the Crescent Moon get a whopping 60' Blindsight at like 8th or 9th.