What kind of rocker shaft is this?

Greetings, Gents. In my dad's stash of parts I found a pair of these rocker shafts (on left in pic). They appear to be plugged on the ends, but as you can see, the ends are smooth & rounded. The oil holes are straight through & appear in-line with the mounting holes.
>> Anyone know what these are? Hydraulic?

I believe the shaft on the right is a 273 shaft with grooves & 2 oil holes. Just happen to have it out.

>> What shaft would be appropriate to use with Harland Sharp roller rockers & a mechanical cam? Thanks!

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