I can't really see what your code is supposed to do, what's with the zipcodes?

Here is an example of how to get data from a file using XML::XPath:

#!/usr/bin/perl -w
use strict;

use XML::XPath;

my $file = 'available_batchnyyn.xml';
my $xp = XML::XPath->new(filename=>$file);

# /AvailableBatch/Available is faster than //Available
my @available = $xp->findnodes('/AvailableBatch/Available'); 
foreach my $available (@available)
  { my $part= $available->findvalue( './Part[1]'); # the [1] is not re
+ally needed
    my $qty= $available->findvalue( './Qty[1]');
    $part=~ s{\s+$}{};                             # you might need to
+ trim all values
    print "part $part - qty: $qty\n";
  }
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