The 140 TTSX, no question. (The 140 XFB worked on moose and many caribou back in the day…never recovered one either.)
While I have shot quite a few moose 'in the slats' (where the 139 would work just fine), I have also had a good percentage of kills involving shots where that bullet would have meant problems if it had been used. 140 is as light as I care to run for moose in the 7mm caliber, and then, only with a mono of some flavor. I would actually prefer 10 or 20 grains more, and especially the latter weights when using a Partition.
