As others have noted the Kubota Grand L's are very different tractors than the standard L's ..... unfortunately from what I've seen they don't seemed to be routinely stocked at dealerships (or at least not in my area).
I suspect the same is true for other brands, though if you can find a dealership that has the premium line of tractors for that brand it's probably worth trying them (if you haven't already).
I'm not exactly short (~6' 2") nor am I skinny/narrow and my
L3560 doesn't feel cramped (I wouldn't say it feels overly roomy, but it's definitely not cramped) ... almost more like a properly fitted glove in some ways (even with my rather long arms).
It does have a treadle peddle, but it's shaped such that it can be used like it was two separate peddles with one being a bit aft of the other (which is how I typically use it).