I did some research, and quickly found this "legal expenses insurance" plan that pays for attorney fees in criminal cases and most other kinds of legal matters. The info on their site says it's about $20/month.
U.S.LEGAL'S FAMILY DEFENDER ™ PAYS ATTORNEYS' FEES
Covered in full Dependent & spouse covered
Consultations √ √
Phone/Office √ √
Consumer Law √ √
Will, Living Will, Trust, P.O.A. √ √
Civil Actions, Plaintiff/Defendant √ √
Adoptions √ √
Real Estate Transactions √ √
Landlord/Tenant Law √ √
Traffic Violations √ √
Preparation of Legal Documents √ √
Juvenile Defense √ √
Family Law *+ 12 Hours √
Criminal Violations √ √Personal Injury √ √
Bankruptcy Chapter 7 only √ √
Immigration √ √
Identity Theft √ √
All other matters ** √ √
* After 12 hours, there is an additional 33% discount
** Covered at a 33% discount
+120 day waiting period
This kind of policy covers almost all legal expenses, not just self-defense incidents, so it might be a better kind of policy. One drawback, though, is that it doesn't pay for bail money, but if you can afford to cover your own bail...
Site:
http://www.uslegalservices.net/legal-insurance-plans