Need to state the hole size(likely metric) and caliper/sketch the form to about +- .001.
With not having a keyway, not for any hard milling.
Could be notching shear blades to notch material such as vinyl and leather.
If so, then they get reground to the minimum size and then go to scrap.
notching vinyl for a curve - Bing
Likely HSS so a decent scrap value, perhaps 15 cents a pound.
I used to sharpen pinking blades that performed a similar task, I would grind them viewing through a magnifying glass down to a .002 land...got $12.50 each so a big-money job. They were about 3 1/2 " diameter, I would circle grind and then come into each facet using the oposite side for the index.