There are prices for passage in various equipment lists, they are all pleasantly consolidated at d20PFSRD.com under "Hirelings, Servants, and Services." Obviously these are base prices and you're welcome to modify them for various in-game conditions.
On the Arcadian Ocean you pretty much need to take the larger ships, galleys and such are constrained to the more stable Inner Sea. So you're looking at a sailing ship, or maybe a keelboat but most of them won't be making 100 mile treks, they'll be coasters going fishing or whatnot. So call it a sailing ship, 2 sp/mile per person (so for 100 miles, 20 gp/ghead). For the carriage and horses it's going to be a lot more - the horses will be 4x a person minimum just based on size. It'd be cheaper to sell the horses and buy new horses when they get there. The carriage is fairly fragile cargo so I'd swag it out at 200 gp.