

Depending on your setting and desired outcome for the poisoner, uraninite (aka pitchblende) might be an option. It has historical uses in glass making and pottery glazing, which could provide justification for why someone would have it.
It contains Uranium, which is radioactive, but I don’t believe will bioaccumulate, but can build up on surfaces, tools, and clothing providing a source of long-term radiation exposure. In addition, it contains lead, which does bioaccumulate, providing a source of gradual long term poisoning as well as radium which also bioaccumulates and is radioactive, providing an additional source of longterm radiation exposure.
Definitely an unpopular opinion, though I don’t disagree with it.
For an additional point of comparison, a brand new N64 cartridge back in 1996 would have been anywhere from $60 to $80. Which based on an inflation calculator would be slightly over $120 to $160 today.
And games are more expensive than ever for studios to make and push to the market. Given that, I’m not surprised we have loot crates, micro transactions, and predatory dlc. A AAA game should have a baseline price closer to $200.