Shampoo recommendations, please???

Hi guys, it's been probably a year or two since I've been on here, so bear with me if the answer to my question is right under my nose and I just can't see it!  (I did read through a lot of old topics to try and find answers, and Google also wasn't doing much to help me.)

I currently have Ion Color Brilliance Brights Teal semi-permanent dye in my hair.  I've used this dye before with Simply U sulfate-free shampoo (mixed 50/50 with water) and had great success with it not bleeding every time I showered (the water always rinsed clear).  However, I can't find Simply U shampoo anymore!!!  I am now using L'Oreal EverPure sulfate-free (as I saw some of you have recommended) mixed with water, and my hair color is bleeding out like crazy! (The water rinses out very blue every time.)  It's only been one week and my color has faded so much that it looks more like it's 2 months old.

So my big question is, do you guys have any other shampoo recommendations for me to use with the Ion dye?  Obviously all sulfate-free shampoos are not equal, but I really don't feel like spending $100 to buy and try every one on the market!

Other helpful info about me:
I live in the USA.
I'd prefer an inexpensive shampoo that's available at Ulta, Sally's, or even Walmart.
I've tried co-washing with little success, so shampoo is definitely my preferred method of cleansing my hair.

Thank you!!!!!!!