State alt name forms.

public class StatePriceChecker
{
    Dictionary<String, int> StatePrices = new Dictionary<String, int>
    {
        { "alabama", 213 }, { "alaska", 523 }, { "arizona", 202 }
        // etc. etc.
    }

    Dictionary<String, String> StateAltNameForms = new Dictionary<String, int>
    {
        { "al", "alabama" }, { "alab", "alabam"}, { "albm", "alabama"}, { "alabam", "alabama" },
        { "alask", "alaska" }, { "alsk", "alaska" },
        { "ar", "arizona" }, { "ariz", "arizona" }, { "arzn", "arizona" }, { "arizon", "arizona" }
        // etc. etc.
    }

    public int GetPrice(String State)
    {
        State = State.ToLower();

        if(StateAltNameForms.TryGetValue(State, out String AltForm))
            State = AltForm;

        if(StatePrices.TryGetValue(State, out int Price))
            return Price;
        else
            throw new ArgumentException(State + " is not a state.");
    }
}