Hi there, and welcome!
Can you tell me the condition of each coin? (Scratches, perfect, "can barely see it", or something else along those lines)
Are you sure that the 1863 gold dollar is authentic, and not a modern reproduction?
Let me know, and then I'll give you some approximate values.
Based on my research, and without seeing the coins in person, here's what I'd say...
1863 dollar coin -- $500
1950 half dollar -- $15
1964 half dollar -- $7
References: http://www.pcgs.com/prices/PriceGuideDetail.aspx?c=51, http://www.pcgs.com/prices/PriceGuideDetail.aspx?c=734 , http://www.pcgs.com/prices/PriceGuideDetail.aspx?c=125
These prices will vary A LOT depending on where you were to sell them. It will also vary quite a bit based on the condition. For example, if your gold dollar coin was perfectly uncirculated (and looked like the day it was made), it would be worth tens of thousands of dollars. However, I don't think you should sell them, as they are likely to become more valuable over time.
Let me know if you have any questions,