If you want quality beam wiper blades, you'll have to replace them each year or every other year. Manufacturers want you to throw the assembly away when the rubber wears out, few places sell just the rubber. Most actually glue the rubber in so you can't get them out.
Known Rebuildable Makes
At Walmart, the Anco beam blades has the spring steel epoxied to the plastic, but the tips come off and you can slide in new rubber. I was able to trim the steel to fit my car with bolt cutters, since they don't make them short enough to fit. At other retailers, the Bosh Icon blades also can have the rubber removed, except the entire spring steel piece can be removed completely after the tips, rubber, and sheath. If you plan on sliding in your own rubber, you will need to trim off the ridge in the center, as pictured below. A dab of lube (WD40) will help get them in. Just remember to wash with dish soap after.
The replacements from Rock Auto that I ordered where not the right type, but some Trico refill kit from Advance Auto were, pictured below.