The price of gpt-3.5-turbo, aka gpt-3.5-turbo-0613 has not been lowered. Refer to the price of gpt-3.5-turbo-instruct, and multiply 2x for gpt-3.5-turbo-16k
Pricing in megatokens
Model
Input usage
Output usage
Context Length
GPT-3.5-turbo
$1.50
$2.00
4k
GPT-3.5-turbo-16k
$3.00
$4.00
16k
GPT-4
$30.00
$60.00
8k
The preview models were to become the new models pointed at Dec 11 - today, but those plans are off.