Nginx location regex and try_files

Trying to set up an inherited nginx to do my bidding, but failing a bit at doing so.

I have the typical nginx WordPress setup:

location / {
 try_files $uri $uri/ /index.php?q=$uri&$args;
}

# pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000
 location ~ \.php$ {
   try_files $uri =404;
   fastcgi_pass unix:/var/run/php5-fpm.sock;
   fastcgi_index index.php;
   fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
   include fastcgi_params;
}

So far, so good. But I also need to check for old URLS from a previous install that follow this pattern:

^(ninos|familia|hogar|mujeres|hombres)(-[a-z-]+){1,3}\.php

And direct those to index.php with its parameters intact, since WP will handle them with a proper 301 redirect to the new URL.

How should I do this? Should I nest another location inside the location ~ \.php$? Or have another separate location block outside, replicating the configuration of the location ~ \.php$? (Minus the "try_files $uri =404"; which I guess it'll break everything down).

Many thanks and regards. Nginx newbie. Tried the docs, but left me confused…