If those hashes live in the symbol table of the package then it could be a simple matter of applying Devel::Symdump e.g

use Devel::Symdump;

require Your::Module;

my @hashes = grep { ref $_ eq 'HASH' }
             Devel::Symdump->scalars("Your::Module");
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Failing that, you could just use call the subroutines that match your specification

my @hashes = map &$_, grep /::get(\w+)Struct$/,
             Devel::Symdump->functions("Your::Module");
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Note that neither of the above examples use strict because of the use of symbolic references.