I replaced my e30 Girling front calipers on the race car with some Centric remanufactured ones last week due to a slightly sticking passenger caliper that was not retracting and dragging the pads, likely due to a disintegrated boot. Before I return the old ones for the core refund I thought I'd take a look to see if I could/might rebuild them just to have on hand as spares. 

These were what came on the car in 2007 and have never been rebuilt, yeah my bad. The insides look better than I thought they would. Inner seals were fine. I was wondering about the pitting in the cylinders which I can see and feel, and the scratches on the pistons (see pictures). I already have the rebuild seal kits in my parts box so wondering if these are "worth" rebuilding?  $$ wise the answer is no due to what I'd get back in the core charge refund minus shipping costs. I guess I'm wondering more about if these are rebuild candidates?

Thanks,

Rich