I looked for these couplers on Sigma Aldrich's web page, and their price varies a lot: 68 Euros for 100g of magenta coupler (CAS 555-21-5), 65.5 Euros per 25 milligrams of yellow (CAS 2044-72-6), and over 200 Euros for 25 grams of blue-green (CAS 2050-76-2). Can you confirm that these are the compounds called for, and if that is indeed the case, what you paid for yellow?

Also, do you have any info on how long term stable these dyes are?