Hi flockleader and welcome to the forum. Lots of friendly people here loaded with expertise and experience. Also, lots of Morgan nuts in the group - I'm one.
As Susan stated, this potentially very valuable Morgan appears to have been harshly polished thus ruining its value; there are what appear to be wire brush marks in the field in front of Liberty's face. Possible value can't be determined presuming it is a problem coin. If it is, in fact an uncirculated 84S Morgan as it appears to be, it would have a value of about $7000 at the lowest Mint State (MS-60), but in cleaned/whizzed condition, its value might not be more than one or two thousand (maybe less, maybe more) although since this is a rare coin and very difficult to obtain in any Mint State condition, it might go for anything. It most certainly WOULD sell, but buyers won't pay anywhere near top price for it in its condition. Also as Susan stated, ANACS is the only certification company which will encapsulate problem coins.
One other caution. I believe it's possible this is a counterfeit 84S. Despite the polishing, I think I detect granular surfaces in the field and on Liberty's face which would indicate a casting although I do not see similar indications on the reverse. Again, ANACS would be the one to go to authenticate the Morgan, but would only slab it if it were authentic.
Stick with the top third party grading services, i.e., ANACS, PCGS, NGC, and ICG for all grading services. They do not switch coins. Other alphabet grading companies, especially the boiler room basement types might be tempted to switch coins, but it doesn't happen very often, even by the rip-off companies. An altered coin such as this Morgan, presuming it has been polished would probably not be switched since the potential value is not worth the risk.