Alloy radiator for 62 Valiant

As the titles says....are alloy radiators availble for a 62 Valiant???
I want to fit a 318/390 stroker in it, and there isn't a lot of room there where the radiator goes, so an alloy one will disapate heat really well compared to a copper/brass one.....coz it's gunna need it.
I can get one locally...about $1000 AUD.....what are they worth in the US of A???
I haven't found any that are of decent qualitly yet from USA sites.
It doesn't need to have an integral tranny cooler in it, as I will use a stand-alone cooler.
Thank you for your time.