You said these are 'thick walled sleeves' - sounds like the tin-can ones to me? Normally what I would call 'thick walled sleeves' are roughly 1/8" thick . . . whereas you're talking about the fact that Egge sells a .083 piston if you pull them out . . . which makes the sleeve thickness about .040 or so (thin wall).
If these are the tin-can sleeves, then you should be able to knock them, out, freeze the new ones and knock them in (from what I know, I've never ran one of these engines). They were designed to be easily serviceable in the field. And, if tin-can, then they are supposedly "ready to run" - though I would think I'd at least run a hone through them.
Let us know what you have - maybe even some pictures.
D