I came up with a cost effective key blank holder for impressioning.
tools / supplies needed:
1 slotted strap bolt and nut (purchased at Lowes +/- $8.00 for 8 ...$1 each!

http://www.hardwareandtools.com/Tie-Down-Engineering-59135-Tie-Down-Slotted-Bolt-and-Nut-Pack-of-8-6160568.html
1 key blank
1 flat file
1 pair pliers
1 bench vise
1 adjustable crescent wrench
bolt label:

bolt and nut, in all their glory

interior diameter of the nut, just over 0.5"

trim it to here

trimmed and filed

wedge the bolt open with a tool its going to be tighter than beggers canyon back home (Star Wars nerd


blank in place. make sure you don't seat it too deep, you will need a little space past the shoulder.

tighten...

make sure the outside edge of the nut clears the shoulder

Ta Da! I wrapped mine in some electric tape to make a more comfortable handle, as the slot is pretty sharp. The neat thing is that the bolt is knurled to help wind the strap, it also makes the "handle" of the holder pretty grippy

Enjoy!