Thanks for the link. The numbers do match at all (1, 5, 6, 9). We’ll have to look elsewhere...
If the attic weren’t full of cranky wasps, I’d go up and check what real Underwood number keys look like.
[it’s raining and they’re all staying inside for the day]
That’s just one Underwood font, though.
There are lots of them.
I would imagine that one of them truly replicates the old typewriter.
http://www.fonthaus.com/products/fonts/view.cfm/sku/VT10050
Totally different style numbers on this one.