Which Headset Bearings...

Just eBay. Headsets are not like LLU MAX. Type so just whatever.

Kinetic are my go to

Trail Vision (Blue Seal) are my go to for all Specialized bearings.

https://trailvision.co.uk/collections/specialized-headset-bearings

Spesh seem to really suffer with water ingress in their headset bearings, weirdly it was always the top bearing to go first on my gen 1 Levo, gen 1 Kenevo and gen 2 Levo, all my other bikes it was the bottom bearing to go first

What i do now on the gen 2 Levo is remove the headset bearings seals and clean out all the old grease and grime with IPA and a airline then dry and then repack with new grease, as soon as they start to feel notchy they get stripped back down and regreased, ive been doing this to the original headset bearings that came in my gen 2 Levo from new (4 years in Oct) and they are still going strong today

I use kinetic for headset bearings, branded or non branded all been good and long lasting, they have a vast collection of almost every size, especially good if the bearing that came with your headset won't slide in after you've pressed the headset cup into the frame, this has happened to me a couple of times now with ZS56 so finding the same bearing dimensions but with 0.1mm smaller OD works a treat, kinetic have been my go to for Enduro and headset bearings, reliable with reasonable prices, quick delivery with no extortionate postage charges.

Another vote for Kinetic. Have also used Aire Velo before too with great success.

Trail Vision (Blue Seal) are my go to for all Specialized bearings.

Specialized Headset Bearings

This. Tom the owner is a friend of mine. If you go that way DM and I'll ping you a discount code.

Enduro, or what ever Wych Bearings have in. I usually shove in some Marine Grease in addition to what's there already.

The Trailvision ones come with Mobil XHP 222  premium marine-specific grease as standard.