The straps you see on my Tank are not Cartier straps, custom from Etsy leather strap makers.
Best to find one that has pictures of Cartier Tank if you are making for that model. The distance between the spring bar hole and case is very thin. Have faced problems at times because there's no good way to stuff the strap into the case. This is also why companies like Delugs deliberately create a line just for the Tank, besides finding buckles that look like the original (though I personally don't care about this last point).