Lettering/color changed around 2005? give or take a year. There's still plenty of them around from IDOCs and folks that had them
stocked away. I've prob got around 40 various gold tag paintings in a chest at home
The large gold tags generally run 500k to a mil (highest I've seen) and the smaller gold tags run 200k-500k.
Prices can vary but that's in the ballpark from what I've seen
Edit : If you find ones that just say "Painting" and nothing else then you found a diamond in the rough. Those are from circa 1998 and are VERY rare.
Last one I saw for sale was at auction about 5-6yrs back and sold for 800m. I'd post a SS but on the laptop atm & UO isn't loaded on it

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