GPU memory costs about $2.5/GB on the spot market, so that is $500 for 200GB. I would speculate that it might be possible to build such a LLM card for $1-2k, but I suspect that the market for running larger LLMs locally is just too small to consider, especially now that the datacentre is so lucrative.

Maybe we'll get really good LLMs on local hardware when the hype has died down a bit, memory is cheaper and the models are more efficient.