I've seen similar. It has trough on the right side. On the left top half, there is windows for additional meter socket. Bottom left has the main electrical panels. You would ned to buy additional kits for the covers to accomodate the other meter socket, etc. These are out dated & maybe against the current codes for wire fill & such. But it may not HAVE to be changed.
As stated above, I would defer to a qualified electrician to have a look. I do know Cali is a license state, as it appears from your info, that's where you reside. As far as price, It could be $4,000. Generally speaking, it's $10/amp for a new service.
Good luck & Happy Holidays