I love the slightly-oversized dice from Role 4 Initiative, so I just ordered a new set for use with Cortex Prime. Quite affordable — only $0.63 per die. I am using different colors for each die type to make it easy to differentiate at the table (and also its great for players new to RPGs who have trouble telling a d10 from a d12, etc.). I’m using Purple for d4s, Green for d6s, Blue for d8s, Red for d10s, and Black for d12s. I’m red-green color blind but these shades are bright and distinct enough even for me to tell apart. Can’t wait to use them in my upcoming Cortex Plus campaign!
You can find them here: https://r4i.us/product-category/dice/