see
http://www.aircraftsecurityalert.com
These people have a MEDECO lock which uses a crosscut key, hardened tumbler, etc. for high security applications. They have one that will fit the Cessna 337. They can also key multiple locks.
This way you can get away from the Cessna locks where one key fits all............... Ideal for Mexico, Bahamas, South America and Washington National.... <G>
Works great (testimony) all for 99$. 800 594 8094.
Bob