Craig - so are you saying that there has never been a model run for ivory gripped 4 5/8" blued SBH's? Meaning those MUST be an aftermarket addition? There's nothing unique or special about a 4 5/8" blued SBH with rosewood grips model 0813 S458n-c (the model that's been around for at least 20yrs) or the 0814 KS458n-C stainless version, but if this revolver left the factory with those ivory grips, it's not that model. It's reasonable to expect they were an aftermarket addition, but it wouldn't necessarily rule out factory ship if such a model existed.
I can definitely be sure that it's not the right box for that revolver - that box end label reflects an original Vaquero. Whether it was mixed up at the factory or at the shop, who knows. Kinda interesting - an 87-73xxx SBH should have shipped in 1995, whereas a Vaquero with 58-0xxxx should have shipped in 2002 - so did the shop sit on old new stock for 7yrs, did it get hung up at the factory, did it ship out of order, or did they cross paths at another shop where an '02 Vaq was in the used rack beside a '95 SBH?
Did you get the owner's manual with it? Is it the right manual? Usually those are stuffed in the top of the box, so if they criss-crossed boxes, you'd think they'd have criss-corssed manuals too.