You should be looking at European boots. size 40 is close to a US mens 7 womens 8. Zambelan, Lowa, Asolo, , Salewa Mountain trainer;s are my favorite. I got a pair of Crispi in Mens 7 from BlackOvis and they are great also. I think the Salomon Quest 4 D run on the small side and you can get them in a mens 7.
Also watch Sierra Trading Post, they sometimes have mens boots in 6 & 7