Well, split the difference at 43 vises.
$2,500 divided by 43 is $58 and change per vise.
Consider the two bigger ones freebies, and maybe there's one or two or three of the littler ones left too...
So, at $58 per, what do you need to do to sell them?
Machine them, paint and assemble.
What is required in the machining? How many surfaces does the machine tool need to touch? How many hours per vise are required for machining?
What's your time worth?
And finally, what would you sell them for, and more importantly, where would you be able to sell them?
Ebay? Lots of hassle.
Craigslist? Cheap bastards.
Here? Slightly less cheap bastards!
And either place, you'll probably saturate the market less than half way through your inventory.
In my opinion, I don't think you're going to make your money back, let alone a profit, by buying the inventory, doing all the machining, then retailing them.
But it could still be profitable. There are hundreds of thousands of hobby machinists that enjoy a project. Buy the whole inventory, package them individually in kits, take out an ad in Home Shop Machinist and Machinists Workshop magazines, put posts on hobby machinist websites, and sell the kits for $125 plus shipping.
Let the end users handle the machining of these high-quality USA-made castings.
-Brad