Are there any mac mini 2023 models still sold?

You can get various 2023 models from Apple's refurb page.

https://www.apple.com/shop/refurbished/mac/2023-mac-mini

Forgot to check there (was avoiding eBay or other used items in unknown condition).

Current least expensive item on Apple's refurb page is a 16 GB, 512 GB model for $999. Exact same thing on Amazon is $799.

Amazon sells new ones heavily discounted.