My area, I can and have played doubles most every day except Mondays and Fridays, and I could play those days too with a few phone calls.
My wife has much more trouble find playmates, but she is also reluctant to introduce herself to groups she doesn't know, and she really does not put a lot of effort into trying to drum up players (phone/text) either. I'm a LOT more social, and have zero problem doing either of the above to solid success.
My point of view, unless you live in a sparsly populated area... there are other players in your area just like you... wishing they could find someone to hit with. You gotta find them and cultivate them. That means when you see a group your level playing, stop by and politely wait for a changeover, then introduce yourself and ask if they ever need another player, or know a different evening or location that more players meet at. Or see below what I did for one group.
Don't be offended if you are the only person that seems to be the organizer/makes all the calls/ does all the texts. Someone has to take the initiative... how much do you want to play?
Of all the groups I play with, and all the different groups I have played with in the past, I would say roughly 30-40% have a rating or play league. The majority don't... which means to the OP, even tho it looks like there are only 250 men... there is probably closer to 600-700 active players, and probably close to 1000 men in the area who play just a couple times a year. That is decently fertile ground.
Last night there were 3 courts of doubles playing... 11 men and 1 woman. My court had 3 league/rated players, 1 non rated (doesn't mean he isn't good, he just doesn't play league).
The next court had 1 league, 3 non. The third court had I think 4 non league... but two of the guys I'm not positive about, but I don't think they do.
Last year, I didn't know anyone at this court, but I heard the best times were Wed night, Sat/Sun morning. I'd heard it was good play, so I drove out one Wed night to scout it. It was a good mix of mostly better players, but all the courts were full. I drove out earlier the next Wed, sat on the bench outside the court, and within a minute someone asked if I was waiting for someone. I said no, we started hitting, joined another twosome for doubles, and viola... I was in.
They are out there OP... ya gotta look and be a little aggressive, but polite.
Also, for the TLS site... it only tracks current players for that year... so you might want to check the numbers for 2014 or 2013 to get a better idea of the number of league players.... plus, a good minority of players play at multiple clubs... so they could be found under 2 different clubs I think.