the problems you will likely have will be on the USA side. Mafai is also in season if you are looking for seeds, Santol will soon be in season, and Mangoes all types are in season. R2E2 is one of the best varieties on the market and often overlooked because Thai consumers shop for color and shape, so R2E2 is a bit cheaper than others, picked up a crate for 50/kg last week. Papaya cultivars also should be looked into, Gaek Dam (many subtypes, all red flesh) and Holland (yellow flesh and large) being superior strains here, and true from seed. If your father hits up the JJ market on the weekend he can pick up any sort of rhizome, seed, seedling, etc.. generally that plant market has everything there is to offer but marked up considerably.