The reason the Bender business cards are perilous is that years ago, A large unsigned group of them were sold as part of his estate with other personal effects.
Its likely that a few maybe even more authentic signed cards exist but since there were so many unsigned ones sold. The odds are kinda against getting a good one.
Since his autograph is not particularly rare you might consider acquiring his autograph in a different format. There are personal checks of Bender that are offered once in awhile and they display nicely.
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