[Request] MI, USA - Looking for first properly fitting bra: 26C/D or 28C/D

I told myself I wouldn't post a request here unless I had something to offer (like bras I've bought in my new sizing which didn't work out), but I've been online shopping for days and can't seem to find something I can responsibly afford (especially since I have yet to verify my size through trial and error - you can't find these sizes in stores).

The calculator puts me at 26D or 28C. I am conical, full on bottom (very shallow on top and in the cleavage region), wide-set, and splayed. So, I am willing to try anything in the ballpark of my assumed size.

Demi-cups, plunges, and push-ups have worked best for me in the past, but what do I know - I've been wearing 34A for 15 years. Hah. I am reading that balconettes would be good for my shape as well, but I have no idea.

I will pay shipping, and anything that doesn't work for me, I promise to pay forward! Same goes for anything I buy in the future which doesn't fit properly.

EDIT: I forgot to mention that I do not care how old or used they are, I just want to find a bra that finally fits me (I am 30 years old and I have -never- had one even close to fitting properly). And depending on how unworn they are, I would be able to pay $5-20 on top of shipping.