You could run your CGI script via command line and redirect the output to a file.

perl myscript.cgi name='user name' dob='September 2003' > need.html
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Where 'name' and 'dob' are the names of the form entities you'd normally fill out/check/click and the strings are the values that would be assigned if you had filled out/checked/clicked said form objects.
UPDATE:
Another monk advised me that this would be a little too much to type on the command line if you had several form elements. So, if you do, put them into a file:

$cat input.txt
name='user name'
dob='Sep 2003'
state='IL'
city='Chicago'
county='cook'
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So the script could be run as:

perl myscript.cgi < input.txt > output.html
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