The 1964 half is 90% silver. As of today, Jan. 24, that coin has $37 of silver in it. Now, dealers are paying considerably less than that because of market risk and the need for profit. So you would probably get $20 if you sold it.
The Sacagawea dollar is worth face value. I spend these. There is a Cheerios variety with crosshatched tail feathers that is most valuable in uncirculated condition. You have no evidence yours came from such an origin; the feathers don't look like they have that feature, and it has circulation wear already.
