The style of this particular glass is often referred to as being 'footed'.
'Footed' glassware was popular and a common style in the early 1980s.
I have seen several examples through the years, almost all of them released in the early 1980s.
One of the most common EPCOT Center related ones being the 'footed' Figment mug from 1982.
I have a coffee mug done in this same exact black metallic finish visual style, but not footed. Just a typical basic round mug.
I always dated it to be late 1980s or more likely early 1990s as I have a collection of WDW merchandise catalogs from 85' through 89' and I don't recall seeing these listed.
The original Park logo was used up until the mid 1990s, so it's difficult to date items based solely on the logo.
Just looking at the fact that this is 'footed' glassware tells me it's probably from the early 80s if I were to guess.
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