Local or regional varieties can be hard to get. For a while, there were no Hawaiian chili seeds locally and they are not sold on the mainland. I can get creole tomato now, but a few years ago there weren't any available. For part of last year and this year some nurseries are already back ordered or don't have kale seeds due to crop failures. It is good to save seeds. Just remember if you are going to do that on an op plant, you have to make sure no other varieties are around that might pollinate them instead.
Happy gardening in Hawaii. Gardens are where people grow.