You could try eBay, or a reputable coin dealer in your area.
Avoid pawn shops, second hand dealers, etc.
There are two variants of this coin. Variant 1 - First bust - Obverse showing George III head and shoulders. A British 1812 silver Three Shilling bank token (George III), circulated but still in good condition, might fetch anything from £25 to £200 GBP. A British 1812 silver Three Shilling bank token (George III)(Proof FDC), might fetch up to £650 GBP. A British 1812 silver Three Shilling bank token (George III)(Proof in gold FDC) is considered to be extremely rare. A British 1812 silver Three Shilling bank token (George III)(Proof in platinum FDC) is considered to be extremely rare. Variant 2 - Second bust - Obverse showing George III head only. A British 1812 silver Three Shilling bank token (George III), circulated but still in good condition, might fetch anything from £25 to £225 GBP. The values quoted are the best possible for the best specimens in their grades, but may be significantly lower due to varying demand for the coin and the prevailing economic climate. A reputable coin dealer will be able to give a more accurate valuation based on inspection of the coin.
The value of an 1813 one half penny token varies by where the token originated.
Well, Based on years of studying the 1813 one penny token, I have deduced that it is worth around $2.35. Yes, that's two dollars and thirty five cents.
George Aspull was born in 1813.
George Hollingsworth was born in 1813.
George Dent died in 1813.
George Worthington was born in 1813.
George Gilfillan was born in 1813.
The last British One Guinea coin struck for circulation was dated 1813.
George Hammond Whalley was born in 1813.
George W. Grandey was born in 1813.
George Windsor Earl was born in 1813.