I'd say have them cut for the woodruff key if you want to, it's not really any longer or shorter either way so long as they have the cutter for that width and diameter key.
The same cutter and setup in the mill will allow them to cut the longer keyways.
2 hr max, might come in under an hour if they're proficient at it and have the tools handy.

•1951 GMC 250 in the Project Journals
•1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
•1952 Chevrolet 3800 pickup
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