From the official website of the Personal Ordinariate of Our Lady of Walsingham, where a copy of the heraldry can be found:
A Coat of Arms has been issued for the Personal Ordinariate of Our Lady of Walsingham. It was designed by Fr Marcus Stock, the Secretary of the Catholic Bishops’ Conference for England and Wales.
The shield is in two halves. The left hand side contains the shield Bl JH Newman’s Coat of Arms, using his motto Cor Ad Cor Loquitur (Heart speaks to Heart). The right hand side is from an ancient Coat of Arms of the Shrine of Our Lady of Walsingham, with the distinctive fleur de lis of Our Lady. The shield is surmounted by a mitre.