Purchased in 2019.  Never used.
Seat Collar:  30.9
Color:  LightBlack
Drybag Size:  17L
$180 + free shipping to Continental US
A new one from Porcelain Rocket, if they have in stock, will cost you about $200 with shipping.  Buy from PR if you can.  Awesome company.
Seat collars for other size seat posts are available from PR.