Hi from Oz

With the right hand exhaust restrictions, putting a 440 in there might mean that YOU will be making the headers.

Yes only 3 options really,
Stock exhaust manifolds regrettably.
Block huggers but I think they will exit straight into trouble.
A while back I bought LHD abody headers four into one 2inch primary into 3.5 inch collectors tack welded together by mad dog headers in the states. Those headers will need some serious modification, probably best to start from scratch.