Keep trying, even when it looks like it can't happen
I don't generally speak about my background, but I'm a convicted felon and thought I’d share some things I’ve learned over the years since my conviction (served time in prison, the whole nine yards). It's been 15 years since I got out, and it still follows me around, though not on a daily basis any longer. You'll learn to live with it and be able to do the things that are important to you; you will just have to work harder to get there and be prepared for many, many rejections along the way. You're lucky to be in a state where an expungement is even possible (my conviction was in NC, where unless you were a minor or meet a very specific set of circumstances, you cannot ever get an expungement...and yes, I've met with countless attorneys and even the Governor to verify it).
I took the opportunity after getting out of prison to go back to school and get my graduate degree (I went to the USMA at West Point for undergrad...which certainly could have helped me to get into a good graduate program even with the felony conviction, but it turns out some schools don't ask the background questions for graduate school applicants). I spent two years teaching at the university while getting my master’s degree in exercise physiology. Ex Phys was an interest, but not something I necessarily wanted as a career (I'm a Crossfit trainer and former competitive powerlifter, so I know I'm not interested in that career field any longer). Instead, I used it as an opportunity to show future employers I had turned the corner and could be a productive member of society again. Once I finished, I was immediately hired at Duke hospital.
I share your interest in SAR, and to that end I first got my CNA license (it was an easy, no questions asked community college course and then I was certified). After that I was able to become a first responder, and then an EMT. My experience was particularly difficult as I had no driver’s license for about 5 years (took a LOT of meetings to get a Battalion Chief to sign off on my EMT application). During that time, and since then, I’ve spent many a weekend volunteering in the medical tents of races (runs, triathlons, charity walks, etc.). For one, I enjoy it. As a bonus, it increases my knowledge in the field, and it certainly looks good on my CV. I’ve had numerous opportunities to join SAR and even SWAT since then (even though they all have policies that say you can’t with my background)…I’ve simply gone a different direction in terms of careers.
I’m now married (to a successful surgeon I met during graduate school), and work in the medical field. For employment, your best bet is to find the small companies that don’t have a human resources department (where you’ll always get the door slammed on you). My best success has been with small, privately owned companies…where the owner makes the hiring decisions. I let them know where I’ve been, specifically why I’ll be an asset to their company, and then appeal to them for an opportunity to prove my worth. My job at Duke hospital was an exception…the department offered me the job before HR knew about my background, and even though HR wanted to rescind the offer, the department backed me and said they wanted me even with the felony background. A huge lesson: never ever lie on your application. If it doesn’t ask, I sure as heck don’t tell…but if it does ask, I have a scripted, short explanation for what happened and what I’ve done since then.
Long reply, but I can feel your pain and just want you to know that you too can turn the corner and find success. If you have any specific questions, don’t hesitate to PM me and I’ll do my best to answer them.