Dear Aravind Sir,
Coconut Varieties. East coast tall, West coast tall ( Tiptur tall ), Chennangi, Kappadam etc are the popular Local Traditional varieties in coconut. For getting Real Seedlings, you have to visit the traditional Coconut belts like Amalapuram, Andhra pradesh state, Arisekere,Tavarekere,Tumkur, Karnataka state, interact with coconut progressive Farmers, inspect their old Mother plants and after ensuring the quality, you can purchase from them.
if you know any local Reputed Nursery, insist them to sell if they are only Traditional Native variety coconut plants only.
or Better purchase Kappadam Variety Coconut seedling from any farmer or nursery by checking the rooted coconut of the seedling, it will be very very big in size, which will be mostly available in kerala, tamilnadu and karnataka, widely.
As regards to papaya, If you want native Traditional papaya variety seeds, the best way is only gathering information in near by villages of your land. Generally keeping quality will be very less in these Native papayas, but for getting very tasty good yielding native papaya seeds, you have enquire only with Farmers/Villagers, but these varieties are not suitable for marketing, up to my knowledge.
As regards to Traditional varieties Banana, like Nendran, Karpura, Chakkarakeli, Amruthapani, Red Banana, Yalakki, the facts are , invariably, you have to visit the nearby farmers lands, check the garden for disease free, quality and purchase the required Suckers , Treat for any diseases and plant in your land. Nendran, Red Banana, are mostly available in Kerala and Karnataka, Yalakki available in Karnataka, Karpura, Chakkarakeli, and Amruthapani are available in coastal Districts of Andhra Pradesh.
wishing you the best,