There are only about a thousand details missing from your post, as Pat alluded to. Also, the square shank, is it a hollow section or solid?
$1800 buys you almost nothing in this day and age as far as tooling goes, especially when constructed of Inco 718. Is there a reason you need such "difficult" material?
It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.