Yes, the player can stock up for each trip to the mines by visiting the Dwarf and perusing his shop. He sells Cherry Bombs, Bombs, and Mega Bombs. We will admit that using this method isn't a very cost-effective way to stockpile bombs. Especially considering how simple it is to make standard bombs when you have the recipe. However, if you get early access to the Dwarf's shop, this can be a good way to get your hands on Mega Bombs even if you don't have the recipe yet. However, as a rule of thumb, we would say try to craft these rather than opting to buy them if you can help it.