I bought one of the target feeders I mentioned above (they're cheap, so worth a shot I thought). Just tried it today. The mysis did fit through, but it was a squeeze. However, as I could just squeeze the rubber ball and suck up some water, that unclogged it. I was able to aim it reasonably well. I did use two hands, but found holding it right at the top, with the other hand on the rubber ball, was enough.
The extension is just plastic, so it the clogging becomes an issue, I plan to just trim a little bit off to widen the tip.
Overall, quite pleased with it.