Thanks. I am disappointed, I thought I'd found a rare one.
I looked at her with a magnifying glass, I agree she is Cha Cha, I can just barely see the original pink cutie mark.
I got her in a thrift shop in a bag full of old ponies, she is almost 30 years old, who knows when she was transformed.
so much for hoping to resell her. oh well, it was fun to dream.