Your best course of action is to try to sell them for a limit price rather than market price, and set your limit price to less than the current market price to make it enticing for a possible automatic index fund purchase. If you're asking a player to purchase stocks that you're looking to dump, you'll need to first share the world you're talking about, and if you're trying to get rid of them there's obviously something unattractive about them so it'd be a hard sell to get another player to take them off your hands.