The best I know of is Mommy Discipline or Ms. Bobbi. I saw her once about a decade ago and her specialty is spanking. I saw her for a role play scene, and out of respect asked her to incorporate some spanking, and she was wonderful. I would have repeated but a long term Mistress I knew reappeared in NYC and out of loyalty I only see her now. Bobbi had a great figure for someone in her mid-50s back then, and from what I can see now, she looks great for someone who's now 10 years older. Here is her website.

https://www.mommydiscipline.com/about-1