KH piston dust seal fixable?

Finally got all the pistons out of the calipers. However, two of the rings that retain the dust seal boots came with them.

Are theses press fit?
Are they fixable?

Bores are pretty good until just past the seal, then they’re pretty rusty and that’s why the retainer pulled off.

FYI, to use a grease gun to force the pistons out, you can easily make a zerk fitting to thread in to the supply side. I just got a 1 inch long bolt in 3/8”-24, drilled a 1/8” hole all the way through it and then enlarged the head end hole to 3/16” about a 1/4” deep. Then just put one of those tap in zerk fittings in the head end. Note - the bolts only seem to be available in grade 5 or 8. So heat em till they glow and let ‘em cool before drilling. Otherwise, you’ll cook/snap a few drill bits. Not that I did that :)

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