The same, but with an unpack:

my $raw = do { local $/; <DATA> };    # inline slurp
$raw =~ s/\s//g;

print map { chr hex } unpack '(A2)*', $1
   if $raw =~ m/0002000000(.*?)00020400/;
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Perhaps a bit too idiomatic, but I prefer using unpack to split characters into fixed widths. It is a tiny bit faster, though not blazingly so:

             Rate  regex unpack
regex    953336/s     --   -38%
unpack  1549170/s    62%     --
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