Have you tried to recruit yourself. I have exactly 10 friends who are now at my gym. Of those, 2 are already sparring, and most likely a few more will drop off as always, but before that there was no one my age. I know it will be harder at an older age and you won't get the same interest, but you never know...maybe a friend, coworker? Sure it may take them awhile to get up to speed, and maybe they'll never spar, but it does help I find to have people close in age, and specifically those I know/knew outside of boxing.