I'v become quite the fan of Costco HA's. It's no secret either. Especially since my experience with the Audie at our local Costco was very good. When my daughter needed a hearing aid, I was able to get the Costco Kirkland Signature 5.0 for her at almost half the cost of what the Audiologist wanted, and he does nothing different than the Audie at Costco.
Now, Costco does sell almost all major brands from Phonak, to Rexton, etc.
However, since you are profound in both ears, I would ask the Costco Audie about their Kirkland Signature HA's. Costco has the new model called "Kirkland Signature 6.0". The Audie there basically told me they are "Resound Linx" branded for Costco at a much reduced price when bought as a pair. They are both designed to work together with their bineural programming. They can both be operated with one remote together for changes in volume, and different programs for different environments, like restaurants, etc. The other neat thing about those HA's, is they have a smartphone app, so you can stream music, and take phone calls directly from your phone without needing a separate intermediate phone clip. The technology is really advancing quickly, and the prices are getting much more affordable.
Also, custom molds only cost $40 each ear. So, in your case, you can have both ears molded for $80. Find a private Audie that will "normally" do it for that price, and I've got a bridge to sell you. LOL Don't get me wrong, Audies deserve their pay, but it is an obvious conclusion of why they usually charge a lot more, being independent. Costco can sell HA's with a much smaller mark up.