Glendale-based African Travel Inc., tel. (800) 722-7755 or (818) 507-7893, trumpets safaris in South Africa's Kruger National Park, with "tribal entertainment" on the big night and sunrise game viewing on the first dawn of 2000. Prices, reflecting the rates set by hoteliers and the company's own interest in making a fair profit, will be 30% to 50% higher than the year before, said President David Herbert. But so far, he added, "bookings have actually been slow." The company's three South African itineraries range from 11 to 13 days. Rates, including air fare, start at $6,795 per person, based on double occupancy. Overseas Adventure Travel, tel. (800) 873-5628, operator of upscale outdoorsy trips, operated four tours during the New Year's Eve just past. Their average cost was $2,615 for 16 days, including international air fare. For next New Year's Eve, the company has 12 trips, with 60% of available spots already filled. The company's average millennial tour cost is $3,873 for 15 days. The two biggest sellers so far: a "Discover Thailand" trip (including Bangkok, Chiang Mai, elephant treks, rice barge rides) for $2,390 per person, including meals and air fare; and "Four Worlds of the Andes," a $2,490 trip to Peru and Bolivia that includes Machu Picchu, Lake Titicaca and an Amazon hike.