An Arc B580 will just about fit Flux.2 Klein (At FP8). However, you can also easily get much larger GPUs on RunPod or Vast at $0.25/hr.

I would strongly recommend exploring that option, renting an RTX 5090 for an evening of image generation for a dollar or two is way more fun then trying to jam big models on little cards. Just take some time to create a reasonable, scripted, deployment workflow for when you create a fresh instance.