Bower, the experienced Crusaders prop, and Highlanders midfielder Tavatavanawai are among a 34-man squad selected for the trans-Tasman rivalry, providing a strong Fiji connection in the New Zealand camp.
Both players have previously been recognised for their links to Fiji, with Bower and Tavatavanawai
Tavatavanawai brings a powerful ball-carrying presence to the midfield, while Bower offers considerable experience in the front row.
The pair will now have the opportunity to feature in one of international rugby's most fiercely contested rivalries.
Taylor has been confirmed as captain for the Bledisloe Cup campaign.
The veteran hooker will lead the All Blacks into the opening Test at Eden Park on 10 October before the series moves to Sydney for the second Test on 17 October.
The squad also includes a mixture of established All Blacks and emerging talent.
Richie Mo'unga returns at first five-eighth, while Scott Barrett is back from injury and Shannon Frizell returns to the squad after his spell in Japan.
Hookers Codie Taylor (capt), Asafo Aumua, Samisoni Taukei'aho will form the front row with props, Ethan de Groot, George Bower, Xavier Numia, Tyrel Lomax, Fletcher Newell and Pasilio Tosi.
