Есть ли сайт, на котором можно смотреть расписание спидботов до островов в Камбодже?

У каждой компании своё.

Вот инфа как попасть на MPai bay.

Prior to your arrival we wanted to let you know that there’s only two speed boat companies that stop in M’Pai Bay: 1. GTVC which leaves Sihanoukville at 8AM, 11AM, 2PM and 4PM; 2. Buva Sea which leaves Sihanoukville at 8:30AM, 9:45AM, 11:30AM, 14:30PM and 5:00PM. If possible, we would recommend taking the GTVC speed boat company as they have been most reliable :).