As of my last update in September 2021, a 1999 $5 American Eagle gold coin in uncirculated condition (no signs of wear or scratches) can be worth around $450 to $500 USD based on the current spot price of gold. However, please note that the actual value may fluctuate based on market conditions and demand for the coin.
To obtain the most accurate value, it's best to consult a reputable coin dealer or check reputable sources for pricing information.