Vintage Bulova 666 bezel repair question

[got2watch]

I'm in the middle of restoring a 1980 Bulova 666 (Devil Diver) and am trying to confirm how to handle the bezel. (see pics)

It was quite dirty and grimy (didn't rotate) but after cleaning and soaking a bit, it started turning and I managed to pull the bezel off the case.

There is no click spring nor retention ring, only a worn out o-ring inside the bezel.  I am concluding that the o-ring is there as a tension ring to hold the bezel in place(?), as the bezel sits outside the crystal, so I know it's not for waterproofing.

Can someone confirm:

1) Did some Bulova/Accutrons from this era have these types of free-rotating bezels with only a rubber o-ring to help keep the bezel attached?

2) Is it as simple as matching the o-ring, applying a bit of silicon grease and just pressing the ring back on?

3) Wouldn't see very sturdy. Is there anything else needed to reduce the chance of the bezel coming off (other than glue)

I've handled "normal" bezels in years past with click springs and metal wire to retain the bezel, but servicing one with only an o-ring is new to me.  I would appreciate any feedback/experience from others.

Much appreciated.