IMHO I don't think it is worth the $500 your asking for it. while the size may be rare, that is simply because there is not alot of 63cm bikes built because there is little demand for them
you often see much newer bike with "brifter" type shifter and 8+ speeds for $500. your Shogun while a nice bike is closer to a $200 bike and maybe a bit less because of the large size.
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