I just ordered some Tylan from www.strombergschickens.comI AM BURIED in Muscoy ducklings. Very prolific good mothers. Message if you are interested.
I text my vet now, but you can still get some things on Ebay.
2 day shipping is pretty pricey but I've got two young birds that look to have an MG infection so I'm not worried about spending more to get it here quickly.