Where to find a transformer for an ARC sp-3?

I called Audio Research and they don't have them/
B1702260 6bfd 423e 90c8 a2314c3e12babaranyi
What about DIY one within the same specs?
thank you Single ended. I considered that route but on another website I was told about Tranformer winding service out of Maine. He rewind the original transformer.