What you could do, until I (or someone) gets a chance to check back on the if-script solution, is to use that script (the one which does lf->cr/lf plus ctrl-D at the end) as a front filter, the way you tried that perl in-line script. E.g.:

cat myfile.txt | filter.pl | lpr

You can check that the cut&paste script works correctly with
perl -c filter.pl
which does a 'compile check' but doesn't execute the script.
Or even just the line above, without the final '| lpr'
(it should just print on-screen and look basically correct)