At one point, there were black HM5 pads that were not as thick. I've purchased two sets (at the same link you posted) in the past few months and both have been thick.
They are super comfortable.
That said, do you want pleather or velour for the 770s? All but the 32 Ohm 770s come with velour, not pleather. Pleather will give you a little better isolation, more bass, and potentially cloudy bleed into the mids. Velour will change the sound minimally from stock. They also have Hybrids that are pleather outside, perforated pleather inside, and velour where it touches you. It's basically halfway between the two in sound changes as well.
I have all of the variants of the HM5 pads except the angled velour. All (but the angled pads) are +/- 1-2mm in all measurements.
What are you using the angled pleathers on and would you recommend them? I'm planning to get a pair for my Soundmagic hp150's.