I know all the ones I've seen from 94 onward have.
All I can add is that I had a 96 in truly mint condition with coa and couldn't move it at $1500. I know from eBay sales and a few auction results I found that they do get that much (close to 1k of silver in them so it's not that crazy a price) but you will have to be patient and find a buyer.
COAs and boxes are a killer with this kind of thing though, I sold a gemstone lunar ox on the forum for $750 (retail $1750) just because it right have it's $8 box and paper slip. My point is its definitely worth finding out if the early ones cane with certificates because of they didn't and you can say this is complete then you'll get a lot more for it.
93 is a good year and more than 20 years old though, I'm sure you'll do ok on it, just maybe not what you might think for something so nice.