is this rear caliper salvageable?

[Bretty]

My rear brake seizes every winter, but frees up with use. I should have serviced it ages ago, but finally took it off today.

One piston moves with force, the other is stuck. I could probably free things up with penetrating oil, a soak and a clean but am I wasting my time?

Is it a case of "new seals, it'll be fine" or "bin it and get a new one"?

I would obviously prefer to fix it on the cheap, but is it a false economy?

Cheers,

Brett