Susan Sarandon's daughter Eva Amurri and hubby Kyle Martino -- received an extremely unique wedding gift last month ... that got lost in the mail -- but luckily one good samaritan sent it back.
TMZ spoke to the do-gooder who says her family was expecting a shipment of speaker wire this week ... but when her dad got the package, it was filled with swag from Eva's nuptials instead.
We're told the return address had been damaged -- but they noticed a stack of place cards which said the couple's names in the letterhead ... as well as a large hat box-sized metal statue of the first letter of both their names.
We're told the family figured out a way to get in touch with Eva's people and are in the process of returning everything to the couple.
A rep for the actress confirms they've been in contact with the family and are waiting to receive the gifts.