My first ereader was an Ectaco Jetbook lite and it was/is pretty sturdy
one of the things I like most about the JBL is that it runs on AA batteries
so add a JBL
http://www.ectaco.com/ectaco-jetbook-lite/
http://www.jr.com/ectaco/pe/ECT_JETBOOKLITE/
http://www.amazon.com/Quality-JBL-EN...2846955&sr=8-1
one of the cases/sleeves mentioned in an earlier post
stick the cased JBL and a 24 count blister pack of batteries (get a reccharger and 2 sets of batteries for home use) into a waterproof case
http://www.waterproofgear.net/
http://www.thewaterproofstore.com/?g...FRNb7Aodmi8Ung http://www.cabelas.com/catalog/brows...ers|USA&rid=20
The JBL will need a book light as it is not back-lit
Jetbook Lite - Recommended Book Light?
https://www.mobileread.com/forums/sho...bl+night+light
Subject: Jetbook Lite - Recommended Book Light
http://www.ectaco.com/posts/list/19458.page
with a few sd cards of books, enough batteries for the JBL, and the book light and you would be set with no need for a pc or outlet plug