Only the part you can see is bronze. All the moving parts of a Goulds are plastic like many of the other brands. There are some brands that have Stainless Steel impellers but, they are so thin that I don't think they will last any longer than the plastic ones. The motor is a very important part, and I don't think you can get a Goulds pump with a Franklin motor any more.
I would look for a pump with a Franklin motor, like the one you have now. Check the prices at www.pumpsandtanks.com for a comparison. There is not enough difference in pumps to be paying more money for a particular name.
Even the brand name pump companies make a low grade version to sell at the box stores. You need a contractor grade pump, and there are a lot of brands that are as good as Goulds.