Denon PMA-880R toroidal potted transformer

Have a Denon PMA-880R where the primary of the power transformer is open circuit. The transformer is a potted toroidal. Any way to un-pot these, and probably get access to a thermal fuse or broken wire? Will simply heating the transformer melt the potting material?

Or if there are replacement transformers available?
 
Yes, seems hard like epoxy. But for the primary there is a connection I have access to. I opened the connection so that I now have 4 wires for the primary. Two of them measure some 10 Ohm DC resistance. The other two is open circuit. Is it likely these are only connection to the fuse buried in the transformer? If so, I should be able to either simply bypass the fuse, or add a new one... what would be a suitable temperature limit for the fuse?
 
In the meantime I did a measurement using a variac, and it definately looks like the primary winding is still ok, it is only the fuse that is buried inside the potting that is blown. If I should replace it, what is the suitable tempreature threshold?