Well, in the Boston area, Fr John Keane at one time had 4 chapels running, starting off in W Roxbury right from when the NO came out. Also in the Boston area, from the early 70’s till his death last year, an Fr Vincent Bowes, O.C.D. said the Mass where he could.
In the Danbury, CT/NY line a few priests had Mass centers going. One of them from way back who is still going in the area is Fr(now bishop) Robert Mckenna, O.P. who says the Dominican rite in Monroe, CT. He has been there since 1973.
In the Chicago area(I don’t know if it is the same priest mentioned in the above post) Fr Martin Stepanich, O.F.M. never stopped saying it and is still with us, well into his 90’s.
Fr Brey said it up in Minnesota. I know there are many others, some who said the NO for a bit before going back to it, others who stayed with the TLM, as well as some who did both.
Joe