Hello out there,

for a similar problem we milled some pins off, added an
intermediate pcb (traces routed to different pin locations)
and canned everything in epoxy. So we got our own "Chip".
Some little means took care, that any intrusion whether
mechanical or chemical would have destroyed the chip ;o))

By the way, many IC´s are available on chip basis. So you
could apply the chip to a pcb and by bonding the chip contacts
to the pcb you may easily apply fuses into some connections.
After programming the chip you could blow these fuses.

If you are a safety maniac, you could also include some
shielding means.

Regards

wolf