In a recent study dealing with Phosphorus digestibility I balanced the diets according to each amino acid, I had to buy each of the amino acids that the feed ingredients did not provide in the right proportions. This option is expensive because the minimum amount of amino acid required in relation to the amount sold. To minimize the cost, I sourced some amino acids from researchers that had related studies and had un-used amino acids. I would suggest that you approach the corresponding authors inquiring if they had some the amino acids that you need. Or which was the source of their mixes? Another alternative is to contact the Research and Development section of the companies that produce Amino Acids. Usually, they are willing to support research. I hope the suggestions will help to overcome your current limitations.

Lysine, Methionine, Threonine, and Tryptophan are easy to find. You can seek collaboration with any local feed mill and I am sure that's they will be more than willing to help.

Thanks a lot Gustavo, those are definitely options I hadn't considered yet. Will contact some companies and ask whether they would be willing to collaborate.

You can also contact Dr. Hans Stein, at University of Illinois Urbana-Champaign , I am sure he can provide you some AA for your research, I could send you some also, but its easier to source them locally.