Japangarden.co.uk are pleased to offer you a wide range of digging tools, hoes, sickles and shears for your garden use. Some of these products are the traditional "economy" versions, standard metal blades which require sharpening in the traditional fashion using a whetstone, others have laminated blades for more professional use.
Traditional Japanese tools are not stainless. The same thing is true today as in years gone by: the best tool blades are made of carbon steel, which simply is not stainless.
However, it requires only a little care to keep them from getting rusty. Just dry them after use! From time to time they need to receive a smear of oil.