here is a link to what your coins date and mint mark are asking on Ebay now... link: http://www.ebay.com/sch/Morgan-1878-1921/39464/i.html?_from=R40&_nkw=1893 O&_sop=15 not sure what your coins grade is ??? VF ? wait for more experienced Morgan collectors opinions....
I sold one this year about the same condition I got 425. For mine. True only 300,000 minted key date coin but the market is full of them in mid grade conditions .
Take it out of the case and go to the Potomac River. Think of yourself as George Washington and try to throw it over the River. If you make it, you're as good as George. If not, well.... Check PCGS facts on the coin and find out the number graded for each grade, then decide to submit or not based on market value relative to what you think it will grade.