ED is well documented among the major oil compamies e.g. Shell and BP etc.
Orings recognised as ED resistant are: -
James Walker FR58-90, (Fluorocarbon based) and Elastolion (Nitrile based). Elastolion grades may need investigation and discussion with James Walker to substantiate their claims.
Dowty 9730 may be out of date as it is prone to premature compression set.
Greene Tweed also have several grades and I can get the details if required, although a search of their web site will revel the products.
Trust this is of use.