DELEGATES from Hongkong preparing to travel to the Pacific Area Travel Association mart being held in New Delhi in a few weeks have just received a two-page document from the Indian Collector of Customs telling the frequently-travelling participants what they may or may not take into the host country. Glancing through the rules and regulations I can see some major areas of aggravation cropping up. Delegates are allowed ''one camera with 12 plates'' and for their listening pleasure ''one portable gramophone with 10 records'' (so best leave the Handycam, Walkman and Discman at home). If you are thinking about a laptop computer, forget it. Only ''one portable typewriter'' is permitted. You are also allowed to bring in ''one tent'', which should be useful if the hotels are full. But transport might be a problem. Delegates are allowed to bring in ''one non-powered bicycle'' and also a ''canoe less than 51/2 metres long''. Probably be a bit cramped up the Ganges.