I have done exactly what you are thinking of in different forms, have no idea if it ever helped but it made me feel much better. I still deliver anti-witness stuff on occasion. Don't put it in their mailbox put it in their paper box if you are in the US. It can take less than 15 min to hit about 50 homes if it is a subdivision. Go deliver a bunch so it won't look like it was you out specifically for her 'study', just some random apostate nutcase! ha, just kidding
(hint-Sunday morning after the large Sunday paper is a perfect time to this because the paper is so large it just fits in the box and you can slip a brochure/print-out in the middle and it is the first thing the 'householder' sees when they get the paper)
There is also a ministry that sends out anti witness stuff with a Christian answer for things, I once had to get a hold of them because I had the wrong address! I think the donation is 5-7.00 (?) at any rate I gave them the correct address and told them to keep the rest of the monies to send wherever they needed to. I was sweating it out I tell you! I would have been found out for sure.
jw-facts has some brochures you can print out so does Silent Lambs, Witness Inc used to not sure now, there are others out there too.