If you're not building the room out from scratch or otherwise moving where the toilet drain is, your options will be limited. The key measurement for replacing a toilet is the rough-in, which is the measurement from out from the back wall to the center of the drain. Different models might have a different relationship between tank and wall, but that won't change your rough-in.
This post has a clear explanation with diagram: https://vevano.com/blogs/bathroom-resources/toilet-rough-in-dimensions
You'll need to see how much room you have forward of the rough-in between the center of the drain and the front edge of the toilet to allow enough space between the front edge and the wall in front. If you're really tight on space, you may need to compromise and go with a round seat model, which honestly is what I prefer. If you're set on an elongated seat, there won't be a lot of difference from one model to another.
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