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You can purchase a Victorian Power Industry (VPI) lock. These can be purchased from some hardware outlets or Master Locksmiths http://www.masterlocksmiths.com.au.
You can arrange a lock by contacting Integrity Locksmiths directly on 1300 366 488. Yes, you can place this on a gate as opposed to the meter box itself.
There is a big price difference between companies for these locks. meterkeys.com.au have the padlock for $55 but Ingetrity Locksmith has it for $117. Can you acccess the meterkeys locks or must we use the Integrity Locksmith locks? Located in 2120.