Brian,
Try Mid-West Natl in N Richland Hills, TX - 800 733-8880 - often marketed as 'Affordable Health Insurance'. You may have a local agent. It is not so much 'cost' but rather 'coverage'. Mid-West extends coverage to on-the-job injuries, most others do not on the assumption that you carry work comp on yourself. If you have opted out of work comp then you absolutely need a carrier that will provide this coverage. It seems that very, very few self-employed people are aware of this potentially devastating situation. I don't know if any others extend coverage to this exposure. You can go with a high deductible and/or co-pay to keep costs down. Good luck - please share outcome to benefit others.
Richard