D2 V8 (4.0) engine wanted

Afternoon,
So after stripping down the engine to change the head gaskets etc, after removing the heads I’ve learnt today that a piston and chamber is damaged so I’m advised to replace the engine.
(I’ve attached pictures if anyone is interested / or has advice on repair other than engine replacement)
My question is then, does anyone know a reliable place to buy a Discovery 2 V8 4.0 engine from? Perhaps maybe just block and heads. I have the rest, which is in working order I reckon.
Cheers

Ouch that looks painful!! Do you know what happened?

its over heated. Wasn’t there when it happened. The Mrs was driving it. But it lost all power and died at the side of the road.
Water pump /thermostat I reckon, had bought new to replace along with head gaskets. But now all new I think.