I'd easily stamp a 63 on that one....even with this smallish internet pic. ..the rims look very nice..

The US graders often gets these wrong...they don't see enough details in the hair in front of her ear,.. and they often jump to AU55 too quickly..IMHO.
I'd also like to see a bigger (at least 800 x 800) sharp pic of this one..The perfectly smooth toning on the obv helps me to go 63 on this one..