when Gandalf died

Other Maiar that lost their physical form used time to reform them, as the case of Sauron at the downfall clearly shows. He used some time to reform his body, and could never again assume a form that seemed fair to men amd elves. If we hypothetize that Gandalf "gave up his spirit" at the summit of Celebdil, his physicalk form, or Avatar, would require some time to reform. That his sword and ring would still be at the peak is no wonder (who would disturb them at the top of the endless stair?). So, when the eagle bore him away, the only thing we cannot account for is his staff..