Hi there,
You have not given any details on your design direction, price target, customer target etc for this brand or how many designs you need - but I am quite sure I can design some styles for you which will sell with all my experience in the market. I have worked for many years for large international brands - Triumph, HOM, Schiesser etc. Most of my experience is in womens underwear & swimwear but I have a fair amount in mens too. I also am now working on my own swimwear range to be launched soon & work with a small factory in Shanghai (where I am based) to produce this - of course they would be able to produce your range also.
Anyway, it is a very small budget for design & I see that many of the quotes are only a few dollars but I would imagine these designers will not have much, if any, experience in men's swimwear & underwear.
For this money though all I can give you is the design sketches (flat sketches) for a small range of items - say around 10 items to begin with and suggestions of fabrics (again depends on your price points) and the possibility to produce with the factory in Shanghai if it meets your cost targets.
Thanks!