With AIX printing you can use the qprt -g 30 flag to start printing at page 30, but not to stop at that point. This only works for ASCII text files where the _d attribute = a for the virtual printer (not formatted PS or PCL)
The head command will only work if you have the same number of lines on each page. Then say your pages are all 60 characters long 30*60=1800 so you use head
qprt -1800 filename | qprt -Pqueue
If you want to use the lp command as described earlier with a shell script interface script, then you would have to use the System V printing mode available in AIX 5.1 and later.
Another option with qdaemon based printing is to write a custom backend. It's not really too hard, or to try to use another filter. You can also do some nice formatting with the pr filter, but it won't meet the needs here.