Double pedal worth buying?

So i was browsing marketplace and somas this double pedal which i thought was a one footed double pedal at first. Upon talk to the seller I was told that the second beater didnt swing, which lead me to believe it was just missing the second connecting pedal and I wasn’t sure how easy it would be to find a replacement or how worth it it would be cost wise. Sellers asking $25 which seems like a steal since they also offered to throw in the pearl pedal next to it, but i’m more concerned about the double pedal since i’ve never owned one, thoughts?