What are the frames at the ends of benches called?
What you have there is the modern soulless crappy plastic injection molded version and the old classy cast iron bench ends. 

Do a search for cast iron bench ends and you will find a world of benches and bench ends from basic to elaborate and ornate.  

Go out a find a pair Paint them black and ad some oak slats, your DIY street cred will go up considerably. 

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