Pat

Iron filter first, and put it ahead of wherever the softener eventually goes.

At 3 ppm you are well past what a softener is happy with. It will strip some of the iron, but iron fouls the resin bed, and a fouled bed stops removing hardness properly and starts smelling. You end up buying resin cleaner every month and replacing the bed years early.

With pH 7.4 and no sulphide, an air injection oxidising filter is the straightforward choice and it will land inside your budget with room to spare. It oxidises the iron, catches it in the media, and backwashes it to drain on a timer. Then the softener you buy next year sees clean water and lasts fifteen years.

It does nothing for hardness. You'll still have scale and still need extra soap. But orange staining is the damage that doesn't come out of fabric, and hardness is the one you can live with for a year.