> Is there much of a market for that?

I don't think it's a huge market, but state-run lotteries around the world need good random number generators for games without physical balls (like Keno for example).

I've talked with people that have created RNGs (rather than buying off-the-shelf solutions) and it sounds like soul-crushing work - mostly due to dealing with the government regulators that need to give final approval before the RNG can actually be put into production.