Curious about your insurance? Your shoes should be covered. All you should need is a prescription from your podiatrist or your endocrinologist. I get several pairs a year. Usually at no cost to me. As a diabetic I seem to meet my deductible early in the year. Even $125 a pair seems cheap though. Mine seem to be twice that much or more!
The pharmacy/ medical supply store should measure your feet, and make impressions. The inserts will be custom made from these measurements and impressions. My shoes always come with 3 pairs of inserts to be changed out at 60 day increments. When I put the 3rd pair in, I go back and get refitted, pick out my next pair, and send in the order. It generally takes about 2 weeks for the new shoes to arrive.
I would not be putting anything in my shoes other than the supplied inserts. I think you will be asking for trouble.
All of my shoes, except the last pair have had the steel in the shoe. The last pair used the Kevlar. All the rest of mine will have the Kevlar as it is so much more comfortable. The Kevlar is more pliable I think and the shoes just seem to wear better. I can take any of my shoes and twist them in my hands. The Kevlar shoes just twist much easier. Just to be redundant, it’s much more comfortable.
Although this is obvious, the only difference between the diabetic shoes and regular shoes is the puncture resistant insole. And often times regular shoes, especially boots, have steel insoles. The inserts make the shoe fit your feet.