You want a kit, not an arf so I would recommend a Great Planes P-51 kit. It will fly great with a Saito 72. I have flown a World/Airborne P-51 with a Saito 72 and it did just fine and it is nearly the same size. There are not too many 40 size warbird kits for sale anymore so your choices are really limited.
There have been several Midwest kits and a few of the Great Planes corsair kits on fleabay recently. Midwest do not look too scale up close but they fly ok and are not hard to build with their flat sided fuselages.
Fred