A simple workaround is to use Google Spreadsheet. Paste (values only if you have complex formulas) or import the sheet then download CSV. I just tried a few characters and it works rather well.
NOTE: Google Sheets does have limitations when importing. See here.
NOTE: Be careful of sensitive data with Google Sheets.
EDIT: Another alternative – basically they use VB macro or addins to force the save as UTF8. I have not tried any of these solutions but they sound reasonable.