Hi Sam,
Some years ago, restoring an Airline, I did the same Google and got what you got, even when I googled 'Radio vibrator'.
However third on the list was an article by an Austrailian which was on point. I think the site is down now, but here are the most important points.
NOS vibrators are usually non-functional. Unlike tubes they go bad on the shelf.
As you know another thing different about vibrators is that they can be opened and repaired. Don't try this with a tube.
They recommend that you clean and adjust the points as bes you can. Sometimes this is enough. Usually it isn't.
That is when to do the 60 watt bulb treatment. The treatment is this. Start by getting it to vibrate on a 6 volt battery or isolated supply. Then rout the current of a 60 watt household bulb through each point of the vibrator. You will see the bulb start dim and then get brighter. the AC spark will clean the point.
I tried it and it worked! I even tried it on the NOS replacement which did not work and restored it, too.
By the way this means that farm radios need to be played occasionally, else they stop working.
I did another quick google searc, and did not find the original site, but did fine this http://cool386.tripod.com/vibservice/vibservice.html. It has much of the same information.
Best Regards,
Bill