I don't know how creative you like to be when it comes to making things, or whether this will even work in your case, since everyone is different. But in my experience, a nice compression top can be made out of pantyhose butts...
Yep.. nylons

...they come in many sizes, colors and levels of compression, and there's at least two reasonably priced brands on display at WalMart or Target. Look on the package for things like "control top"... Your size is probably C or Q (A,B,C,Q... mine is B)
You cut off the legs and wear them upside down, with the neck hole being where the little patch between the legs was.
Depending on what works for you, you can layer, esp on the "trouble spots", and once you have something that fits, stitch them together with lycra thread (sold at craft stores for making jewelry... you might have to split up the string to make it thin enough). You can solve the uniboob problem by making a few stitches with regular thread vertically down the middle, so that the material puckers up and forms a little dent between the umm.. boobs....that can also be done with lycra, depends on what does the job for you....
You mostly have to do the sewing while it's on you, so you might need some help with the back side. To keep yourself from being stuck by the sewing needle, put a strip of copier paper under, between the skin and cloth.
Also, to keep the leg hole edges from curling up on the shoulders, you can use clear silicone from the hardware store plumbing department.... but you'll have to use something like a small or even a 2L soda bottle to put in the holes while applying silicone and while it sets. Use saran wrap over and under to make the silicone have a smooth surface. It also helps stop ripping in places where you trim the cloth. You may need to have a stiffer edge below the breast for it to fit comfortably.
Sure, it takes work and some understanding of the material, but in the end, it's quite a bit cheaper than any of the specially made compression shirts... i mean, women's compression tops are ~$25, men's gynicomastia vests are ~$100 and the thing i'm talking about can be made for as little as $5

While it doesn't look like something you can sell at the store, it's good enough for me in this economy. Ghetto or not, spandex is spandex is spandex. If the scratchy surface catches onto tee-shirts, one can take an old one-piece swimsuit and use that as raw material for the top layer.
Anyway, have fun. Whether you do this or the rib brace, i hope you'll find something that works.
Take care

-Xx