I have seen batignoles vertical in damier, in LV shop!!!!

those are special orders. all store received a few. you can't actually buy them, they are only for display in case someone wants to order them.
 
Yes, it's 30% additional. I'd ordered my Cabas Mezzo in Damier a couple of years ago. It was 30% additional of the original monogram, and I'd waited 6 months for it. I also have to put down 50% of the price as a deposit.