[Reily]

Does it even have a near-species relative still around in Australia? From the standpoint of taxonomy what’s close? The Taz & Wombat looks-wise seem a stretch.

[Blurb2350]

The Tasmanian tiger's closest living relative is the numbat. It's endangered itself, which would make surrogacy even trickier.

[Boogieman]

Tasmanian devil is pretty closely related despite the appearances.

Upon further research, this might be the best choice:

https://australian.museum/learn/animals/mammals/spotted-tailed-quoll/