If that post only a the 'rubber' issue, I would still ride it.
But, looking closer at it, my eyes are seeing a stress crack starting at the lower section where the broken rubber/carbon connection is and runs down and over in an L shape.
I'd prolly take that post off as soon as possible.
Replacement - any 27.2 post will do, just a matter of what you prefer... setback, clamping method, etc. I prefer 2 bolt systems because micro-adjustment of seat rail angle is easy. I prefer fore-aft adjustment over side-by-side clamps.
I have a bunch of different Specialized CF posts most I like, one model has a single bolt using side-by-side clamps. Specialized even puts a note on the post to be sure to lubricate/grease the side clamps.
After a while they still make creaking noises... lubing only helps for a short time...
I prefer and have a bunch of the older model with Zertz insert - sturdy, good adjustment, I've got thousands of miles on them and they hold up, work well and never creak...
One is going on 20 years old and still no issues.
can be had 'used' in the usual used marketplaces online.
Ride On
Yuri
This is one I like best
This post/head, below, is the one which starts creaking on me, a month of riding after I lube the cups, as recommended... Don't remember if mine has Zertz... It's buried at the moment... I need to get rid of it...
