The Shichibukai was a group of seven powerful and notorious pirates allied to the World Government. As a group, they were one of the Three Great Powers that kept the world in balance.
Due to their alliance with the World Government, every member’s bounty was frozen and they had significantly more leeway to commit crimes. However, after two members had each attempted to perform a coup on a World Government country (with the latter member succeeding) as well as commit genocide, they were stripped of their titles and Marine Admiral Fujitora led a campaign to remove the Shichibukai system.
Fujitora achieved this goal during the most recent Levely, as the council of rulers voted to abolish the system; the five remaining Shichibukai at the time immediately had their bounties unfrozen and became enemies of the World Government once again.
In my opinion those bounties will be:
Kuma: 296 million berries. No changes, he’s completely under the Government’s control.
Buggy: 500 million berries. It may seems a joke, but actually to the navy he is a former member of Roger Pirates, a Yonko’s friend and one of the main causes of Impel Down’s mass escape. Plus there is a comic side too.
Boa Hancock: 750 million berries. She is probably the second/third strongest woman in the world, can use all the 3 types of Haki and is the ruler of an entire Island.
Edward Weevil: 1.3 billion berries. He is incredibly strong, should have a top tier Yonko Commander bounty. It’s not higher because he doesn’t have a crew and actually his goal is to destroy the remnants of the Whitebeard Pirates, so it’s not a direct danger to the World Government.
Dracule Mihawk: 2.1 billion berries. He is surely a Yonko tier, but unlike them he doesn’t have territories nor a crew. Also he didn’t used to do criminal acts when he was a Warlord. So I think that a bounty slightly lower than the most recent Yonko Blackbeard is fine.
Donquixote Doflamingo: 1.5 billion berries. If he were still free, I think that his bounty would be very high due to being the most important broker in the crime and because he knows the secret of Mary Geoise’s Treasure.
Crocodile: 324 million berries. The navy stated that if he wasn’t a Shichibukai, his bounty after Alabasta’s events would be at least doubled. After that, he escaped from Impel Down and played an important role during Marineford. I think that multiplying x4 his original bounty should be fine.