Yep it was a mistake, and they admitted such. I thought of small claims but for a then old 10 speed bike no longer made, i figured i'd squander more time and effort than the cost of replacing it.
Small claims court is self serve, no lawyer needed. It's as simple as filling out a form and plonking down $75 or so. And you can add that fee to the damages so it costs you nothing.
And usually it results in either the company completely ignoring you (you get a default judgement in your favor) or they just write you a check to make you go away.