Can anyone help me identify this lovely rose planted by my late wife. It is a shrub rose and I think a Graham Thomas. Thank you.

My first thought was that it was an Austin rose, but I can't name it.

Maybe Molineaux -- an Austin Rose.

I think Molineux and Graham Thomas are both good guesses, based on the color and form of the blossom. GT will generally get to well over head height, often topping out at near 10 feet high, even when trained as a shrub. Molineux, a GT seedling, is a much shorter rose.