If your question relates to copyright issues or Ts and Cs and re-publishing what you've already written: it's obviously a legal matter and I'm not qualified to comment. If you're allowed to link to them from elsewhere, the following may be helpful.
If you're after a platform to get noticed and improve your odds of getting better gigs I would recommend https://medium.com
You can tag your work, popularity is algorithmic, you may show up in people's streams or the Editor's top picks or email digests curated for you. Finally, you can put your bio with contact details or other work or personal website. Do explore that.
Example: (No idea who this is but he is coming up as 'popular' at the time of writing this answer). https://medium.com/@jacobward
You can see his bio refers you to his Wordpress site where he owns his profile. You may be able to link to the end client directly from your bio on Medium.com or if you prefer to your own site where you can point to, allude or directly link to the entity for whom you've written.
Again, I cannot comment on the legalities of claiming ownership of an article that cannot leave a publication, as they presumably own the content. So best consult a lawyer, esp. if there are straight up copyright, NDA or anonymity policies with either your middleman entity or your current end-client.
Anyhow, I do hope this is somewhat helpful and wish you the very best of luck.