If you move to Italy, talk to Guido Bassi, Bassi Vivai, Via Tonello 17, 12100 Cuneo, Italy. He's one of the most knowledgeable Italian growers and researchers. He is always up to date on the latest chestnut news in Italy. Italy has some special challenges. It's a huge producer of chestnuts but Italian growers are dealing with chestnut blight, root rot and gall wasp and they really need to get some new hybrid trees that can deal with root rot and blight. The Italians and the French have been working on hybrids since the early 1990s because the pure European trees often have problems with blight and root rot.
For zones 5 and 6 in the Midwest, the best source of grafted trees is Greg Miller at Empire Chestnuts in Carrollton Ohio, He has a website. He has more varieties than anyone else. The best source of seedling trees is probably Tom Wahl at Red Fern Farm in Iowa. He also has a website. Tom grows a few really good varieties of chestnuts next to each other and the seedlings thus have really good pollen parents. Jenny is one of the best pure Chinese chestnuts you can grow. The tree is vigorous and taller than the average Chinese tree. The nuts are much larger than average but one of the first nuts to drop in the fall. And they have much better than average flavor. Szego (photo above) is a complex hybrid, mostly Chinese and Japanese, that has very large nuts with exceptional flavor, The tree is larger and more vigorous than Chinese trees. It is also very cold hardy. It does have some susceptibility to blight but so far it has never exhibited any serious blight infection. Luvall's Monster is another hybrid (Japanese?American/Chinese) that has very large nuts that also drop early in the Fall. It is very cold hardy. The nuts have very nice flavor. It has some susceptibility to blight but I don't think blight has ever killed a LM tree. The nuts do often have split shells so its not a good commercial tree but it's still a good tree to have for yourself. Tom Wahl sells seedlings of LM and that is a very good option. Other good pure Chinese trees are Gideon, which Greg sells as well as Shing, Hong Kong, Kohr, Peach, Qing, and Sleeping Giant. In the future Greg will be selling Jenny. Greg also sells selected seed nuts which is the cheapest way to start a new planting of chestnuts. Szego is sold by Rolling River Nursery in California and Washington Chestnut Company in Washington.