If you can find one, an engine guard bar can be a leg/life saver: the bike will slide on the guard bar, not your foot, and the bike will not drag you down the road, by your leg! They will also protect the bike's engine a bit.
I've had four low-sides in my life, thus far. Two were on my Honda. Two resulted in pulling nearly every muscle in my body -- got narcotic pain killers both times. Last time was the fastest: ~40 MPH. I slid with the bike for some distance, then I realized I'd better let go. The bike sailed away from me, and went quite a distance after I stopped.
Even the inexpensive gear will save you. My son was my passenger, wearing an $80 armored jacket from Leatherup.com. He ground through the sleeve, and halfway through the foam armor pad, but his elbow was untouched. He had road rash on both thighs, and buttocls (wearing blue jeans only). My chaps protected me, as well as my armored jacket -- I had a small scratch on one knuckle, which was my only injury.
Chaps get a lot of bad press (I've seen the gay guy wearing chaps, and nothing else, please don't post it, or any such -- Thank You!), but they work, and they are very inexpensive ($70-$80 for a basic pair).
I would rather be laughed at, than cried over. YMMV. Cheers!
1979 CB750K (sold, 2012, but not forgotten)
1983 Kawasaki 440 LTD Belt Drive (sold, 2011)
1993 Kawasaki Voyager XII