Among the vendors that sell the product Hex Nut 5, how many of them have a good credit rating?
good credit rating refers to CreditRating between 1 and 3
SELECT COUNT(DISTINCT T3.Name) FROM ProductVendor AS T1 INNER JOIN Product AS T2 ON T1.ProductID = T2.ProductID INNER JOIN Vendor AS T3 ON T1.BusinessEntityID = T3.BusinessEntityID WHERE T2.Name = 'Hex Nut 5' AND T3.CreditRating = 1 AND 3