safaribookings.com is booking engine for basically all operators, and will have the prices listed there.
you dont have much of a choice in the experience of disneyland or not. consider that a safari is a guide driving you around large parks, no operator has exclusive routes or knowledge or land or animal access. the drivers have CB radios and they share info with eachother so if theres a spectacular viewing (like a lion feed) and there are other jeeps nearly its inevitable they will converge in the same spot. but no, its never like a bukakke circle.
when picking a safari package, youre really just picking the driver. the exact itinerary, the quality and style of lodging (traditional hotel, treehouse hotel, in-park luxury lodge), the food (prepared by hotel or accompanying cook), are all dictated by your schedule and budget, and are common across all operators. if you want to see parks A, B,C in succession and paying midprice accomodation and another party does the same with another operator... youre likely to see their truck next to yours at the hotel each night.