I think 338 or 339 is a good point to start. This is the end of the Election arc and the beginning of the current arc.
If you plan on reading it in English, then make sure you find the Viz adaptation, I think EamonX posted a link a few pages back.
The Dark Continent Expedition Arc begins with Chapter 340.
Viz' versions of Chapters 341-349 are exceedingly superior to Mangastream's disastrous scanlations. You can find them here.
I didn't think anyone had rips of Viz's stuff since all the manga sites just grab the first available version of everything, and that's usually a scanlation. Where do you get this stuff?
But yeah, I recently came into possession of a Viz subscription, so starting from about 350 I have access to the new chapters officially translated. If I can guess which issues they are in. It's really not a good system. The huge missing backlog of chapters of just about everything between sold volumes and available new issues makes it pretty much impossible to get in to this without pirating some content unless you're willing to wait a very long time, paying Viz money while not actually being able to read the new stuff you pay for. And only being able to get single issues rather than single chapters is awkward since I have to look at shit like Toriko and
Boruto to get to my precious One Piece. And this means if I want to read chapter x of something I have to look up which issue of Jump it was in, rather than just find that chapter number. It's pretty bare-bones and a very poor business model - buy things in this very specific and not very logical way or not at all - it's like they want people to pirate.