I bought this last week, received it on Saturday: an Anoka County Road 10 shield.

Anoka and Ramsey County 10 are the former alignment of US-10 in the northern Twin Cities suburbs, before the freeway between MN-47 and I-35W was completed in 1999.
This sign was made by a contractor a couple years after that, judging by the sticker on the back.

This next sign I've had for a couple years now, but it's relevant to the above sign: a MnDOT US-10 shield.

This one appears to have never been posted in the field, since it's in really good condition and it lacks the impressions of washers around the mounting holes. Interesting to note that the date code near the bottom center, "799", indicates it was fabricated in July 1999, which is pretty close to the time that the aforementioned freeway section opened.
Here's a closeup picture of the date code and the MnDOT logo at the bottom center.
