When I had to replace the left front on the '74 after trying to fix it for years, I got a reman from either Autozone or Oreillys. So far, so good, but it's only been on there for about a year.....and ya'll know I don't drive it much, so...
From what I know, ALL the remans for these calipers are stainless steel sleeved. It's possible, of course, that some suppliers aren't sleeving them(China), so it's a good idea to ASK the salesperson before purchase.
The front calipers on the '74 were sleeved when I bought it....don't know where they come from, but the left front had always been a leaker. I rebuilt it several times before I found one of the piston bores had been machined off-center.

Every time the piston retracted into the bore, it would nick the seal, until it would finally start leaking.
So, yeah...buyer beware on the remans.
btw...most, if not ALL of the calipers sold by the Corvette vendors come from Lone Star Caliper here in Texas...right down the highway a bit from me. They do NOT sell retail. I tried a few years back to get a distributorship for them, but their demands were just too ridiculous.
|UPDATED|1/3/2017 8:22:11 PM (AZT)|/UPDATED|
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Joel Adams
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"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"