Here's a pro-shot of 'Sara' from the Tusk Tour (courtesy of 'TheSuperFleetwoodMac') who had posted this before, though it seems it was later taken down. Don't know the exact show date.
Interestingly, when Billy Burnette and Rick Vito joined up in 1987, Christine and the rest of the band gushed about them. She said how fun the new guys are, and complained how Lindsey never used to smile on stage. Not sure about that - Lindsey and Christine look pretty lovey-dovey at the 4:38 time-mark.