Well, I just had a fantastic experience with Keysight support today (no sarcasm).
I am lucky to be able to use my friends business name, so that changes things, but still, I was surprised.
I recently purchased a second hand 85032B Type N cal kit. Some of the labels on the connectors were rubbed clean along with serial numbers, so I sent them a message asking if they can check the calibration history (it was last cal'd in 2010) to see if the serial numbers were written down in their records.
They got back to me within the hour and gave me all the serial numbers they had on record, which gave me the missing ones I needed.
We had a back and forth in the chat in the Keysight portal in near real-time as I had a few other questions too. I was expecting a day or two between responses.
They weren't forthcoming with the old calibration paperwork though, but I wasn't expecting so due to privacy issues re. the previous owners details etc.
So, special thanks to Sugiyama-san in Japan KeysightCare for the awesome help!
Now I can get the replacement label stickers I'm drawing up in Adobe Illustrator all finished up.