It's impossible to give you an accurate value for a 1793 Sir Isaac Newton Halfpenny token without more information. The value depends on a number of factors, including:

* Condition: Is it in excellent condition with no wear or damage? Does it have scratches, dents, or corrosion?

* Variety: There are multiple varieties of this token, some rarer than others.

* Metal Composition: Is it copper, brass, or another metal?

* Rarity: Some tokens are simply more rare than others.

Here's how to find the value:

1. Research:

* Find a reliable coin reference book or website: Many resources specialize in tokens and medals.

* Look for images of the token: Compare your token's design and features with images to identify its variety.

* Research the metal composition and condition: This will help you narrow down the potential value.

2. Get an appraisal:

* Consult a professional numismatist: They have expertise in valuing coins and tokens and can provide an accurate assessment.

* Attend a coin show: You can get free appraisals from dealers at coin shows.

Remember: Online auction sites can give you an idea of prices, but they don't always reflect accurate market values. It's best to consult with an expert for a professional opinion.