There is no 83(c) election. At the moment of vesting the amount is considered regular income (no RSU * market price on that day) and you pay taxes on that. A portion of shares is withheld and sold to cover taxes but you may owe more. When you sell you pay capital gains tax on the difference, short or long depending on how long you kept it.
There is no work around, you just keep in mind taxes when calculating your grant worth.