You could find a nice straight 318 driver barracuda for around $10-$15K then drop a crate hemi in there for $15k then figure a few more $k to get it rolling. Now you have a driver hemi for $30k and you can work on the conversion details as the $$$ comes in and as you burn the tires off it.
Last I saw, a real numbers matching hemi hardtop was north of $175k Clones done up right are $70-90k
$30 k doesnt' get you much, but with some sweat equity and not caring about matching ##s you can get a nice car.