/6 to V8 questions

I have a 1974 Duster with slant 6, A904 tranny and 7.25 inch rear end. The car runs great and looks great. However, stomping on the accelerator just isn't much fun. So, as a rookie to Mopar, if you had $5000 to add a V8 to this car, how and what should I do? I realize that the tranny and rear end are light duty and would have to replaced too--hopefully later. I was thinking of a crate engine (from whom I don't know). I would prefer an engine type that could be bolted directly to the A904 for the time being to keep modification costs to a minimum. Or, should I find a donor car and pull the V8, tranny and rear end out of it? As I understand it, my stock front suspension will not work with a V8 transplant. Correct? I guess the last alternative is to ditch this car and start over. Thanks for any help here.