Paper tape reader reels or spools

These are reels for 1" tape storage and transfer, intended to fit paper tape equipment with 1/2" spindles, as per ISO standard 3692.
The tape reader photo shows an example of a machine intended for this style of reel.

The smaller side are used for a 153mm (6") reel, the larger for a 216mm (8.5") reel.

The reels can be used directly with tape by folding a few millimetres back on itself at the end and fitting that in one of the hub slots, then winding a full turn to lock that in.
Or, a tape roll with a standard 2" core will fit over the hub. To allow that to be driven without slipping, fit small strips of rubber in the four shallow slots in the hub. Those should engage with the notches inside the tape roll hub

The hub is common to both the small and large reels; the sides are twist-to-lock on the hub.
The hub is in two identical halves.
The halves can be fixed together either using:
M4 countersunk screws (drill out one side to 3.5mm and the other to 4mm, then fit 20mm or 25mm screws f