We don't have synonyms for chocko yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are chock, choco and chocky.
(n) :
(Australia, obsolete) Alternative form of choco (“militiaman or conscript; chocolate soldier”). [(countable, Australia, obsolete) A militiaman or conscript; chocolate soldier.]
(n) :
(Australia, obsolete) Alternative form of choco (“militiaman or conscript; chocolate soldier”). [(countable, Australia, obsolete) A militiaman or conscript; chocolate soldier.]