Digium hasn’t shipped an analog card containing that chipset in years. Digium has long since marked the older TDM400P card as end of life.
Digium replaced the TDM400 card with the TDM410 card.
Currently, it appears as though there are a number of firms manufacturing clones of Digium’s older TDM400 design. Just because the card reports an identifier that matches the identifiers that Digium used for the TDM400, doesn’t mean that it’s a genuine TDM400 from Digium. Further, Digium encourages you to investigate the TDM410 as it offers a number of improvements over the older TDM400 design.