What is a realistic ammount of time to wait?

I payes for a case that debo 006 was selling on 7-29 (fri) and he said he wouls ship it on tuesday. I was okay because i didnt need it right away. Its been a while and I haven't seen that ups truck. I wanted to PM him but he is banned so no help there either, and Ive checked his feedback and its mostly all positive (97%).
So my question is howblong should i wait before posting bad feedback? And what can I do about it?