Found it, but also found these things are available new online for $15-30, up to you
edit: I also don't have convenient access to 12v to test it but I don't recall having a CEL for it when I drove my donor home so I don't necessarily have reason to believe it doesn't work.
edit edit: ~$10 is what I'm seeing for mailing a 1lb 6"x6"x6" box from my zip to Omaha, cheapest/slowest (<8 days)
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