Ebay offers many TI-99 related item. In the last months I have tried to optimize the search strings in a way that even items are included in the results that aren't captured within a standard search. Many sellers post items without the 99 or even write Texas Instrument and forgetting the s at the end. I will continue to optimize the search string even further.
Another problem is that sellers often limit their shipping area to the EU or the US. If you only search with your account on the ebay application of your country, you will limit your search greatly. If you really want to have an item, that the seller doesn't ship to your country, try asking a friend or a guy from the TI community.
The purpose of posting these search string is that this items will find a new home and don't get banned into the trash.