I found a stainless inner pot for my CPC-600 on Amazon a few years ago and I love it. It's not made by Cuisinart but it's heavy duty with an extra-thick bottom.
This one is not the exact one that I bought but says it's compatible. https://www.amazon.com/Combo-Stainless-Compatible-CPC-600N1-Cuisinart/dp/B08W3QX25R/