Are there IOU markets for $EIGEN? If so, how does one access them?

yes - https://app.aevo.xyz/perpetual/eigen

Coinbase launching one for international -

Founding Engineer shadow.xyz | Values-Aligned Communities | citizen of Black Rock City

Checking the chain @witness - icebreaker.xyz/osprey.fc

yes - https://app.aevo.xyz/perpetual/eigen

Coinbase launching one for international - https://x.com/coinbasetraders/status/1803068013169578433

Big price discrepancy from here: https://coincodex.com/convert/eigenlayer/usd/

Are you looking for something like this? https://pro.whales.market/pre/Ethereum/EIGEN