You can get larger Tricho Hauscha species/hybrids, the plats you speak of are probably more in the clumping Echinopsis category. True T.Hauscha is quite a large plant up to 4m tall.
These type of hybrids are still pretty rare in Australia but that doesn't mean they aren't out there. There is nothing stopping you from creating a hybrid between a large Tricho such as Peruvianus or better yet Terscheckii and crossing it will a clumping echinopsis with a peach flower and creating your own.
I am going to do a few crosses this season that should produce good results, I will keep you in mind when the seed arrives...
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