I'm not an expert in your local area, so I won't try to advise you on specific rates. However, your point about time and experience is entirely reasonable: the job you have been doing, apparently quite successfully, sounds like a technical team lead. That is probably about the same as "Senior Software Engineer" in the pay stakes at most businesses, if they're big enough to distinguish the roles.
One other point that I haven't seen mentioned is that you don't have to try to fix your entire career in a single jump. There is nothing wrong with taking a respectable job at a respectable pay rate with a decent company as a first step, even if it's not immediately at the level of responsibility you were on before. You'll still get a lot more money and better working conditions. If it's a decent company they'll see your potential and grow your career rapidly anyway. Crucially, you'll also have another group of coworkers to ask for references down the line, if you do decide to move on again in a year or two rather than move up in wherever you go at this point. Don't assume you have to try to jump from an awkward position right up to the manager at Google/Facebook that someone else mentioned all in one go: you probably won't make it, and you'll be ruling out a lot of potentially useful opportunities.
One other point that I haven't seen mentioned is that you don't have to try to fix your entire career in a single jump. There is nothing wrong with taking a respectable job at a respectable pay rate with a decent company as a first step, even if it's not immediately at the level of responsibility you were on before. You'll still get a lot more money and better working conditions. If it's a decent company they'll see your potential and grow your career rapidly anyway. Crucially, you'll also have another group of coworkers to ask for references down the line, if you do decide to move on again in a year or two rather than move up in wherever you go at this point. Don't assume you have to try to jump from an awkward position right up to the manager at Google/Facebook that someone else mentioned all in one go: you probably won't make it, and you'll be ruling out a lot of potentially useful opportunities.