they may not due to copyright issues - unless you can just go and do it yourself and then pay for the paper you use.
Sometimes the papers are printed in a way that you won't have room to redraw the seam allowance. This is not a big deal if you remember that you need to leave more on the edges than you have paper for.
I've enlarged and reduced quite a bit, as long as you keeping in mind that you are reducing the finished size and then add back for seam allowance, it works fine.