But I've just posted a custom Garmin Routable map of the E.F.R. OHV area over at www.gpsfiledepot.com
I couldn't fnd anything myself, other than the GIS data from the Deschutes National Forest which is what I used to build the map. This is a routable transparent map with the same color coding as the pdf map generally available online. So you should be able to overlay your topo maps or what-have-you. Myself I use a pretty cheap Garmin Nuvi for riding and find the routing capabilities priceless. I even have it wired to my helmet so I can hear turn by turn directions coming up. Pretty sweet! And the screen is big enough you can see it while riding. Anyway let me know if it doesn't work for you or would like to see changes. I am planning my first trip out there maybe in May??
Have fun out there.