TMTOWTDI.

As dorward says, you can use an AoH:

my @aoh = ( \%hash_a, \%hash_b, \%hash_c );
store \@aoh, 'AoH.sto';
# ...

# elsewhere...
my $aoh = retrieve 'AoH.sto' or die "failed to retrieve stored aoh";
my $hash_c = $aoh->[ 2 ];
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...but you can also use a HoH:

my %hoh = ( a => \%hash_a, b => \%hash_b, c => \%hash_c );
store \%hoh, 'HoH.sto';
# ...

# elsewhere...
my $hoh = retrieve 'HoH.sto' or die "failed to retrieve stored hoh";
my $hash_c = $hoh->{ c };
[download]