If you haven't already search for 'unicorn', 'unicorn hunters', couples dating together, 'triads' 'vee's.
Possibly a reason you've had views and no replies is that what you and your girlfriend are looking for is rare to find and hard to sustain. You two are what poly folks call 'unicorn hunters' - unicorn because finding an attractive, single, hopefully bi young woman who is hopefully into the both of you is so difficult as to be, well, mythological. It's not impossible, but hard enough that you and she need realistic expectations for your search. There is a stereotype about unicorn hunters that you will need to understand and counter.
Have you connected with your local poly groups? There is probably one at least somewhat near you two. If you search about on this site, there are mentions of websites to find local groups. You can also google poly local groups and see what comes up. Having in person interactions is the best way to meet like minded poly folks as well as meet possible partners.
Finally, your last sentence would prevent many from contacting you and your girlfriend. One part of the stereotype of unicorn hunters is that they want a sexy young thing that will also provide free childcare and/or housework. At the least hint that you would expect that, well, unicorns run away fast. I get that you were probably just saying that you two do not want a free loader but your wording was unfortunate and needs changing.