I have sponge , heat pack, paypal and ship...This is the sponge .
I would also say you are probably best going with these guys as they have developed their sponges in a fishless atmosphere so it is guaranteed disease free...
Biologically Active Sponge Filters for Aquarium
My fish room is healthy , but this is sound advice.
If you do not want to order from them or they like most now won't ship $17.50 for one and I will ship to you tomorrow with all the fish I will be shipping !
I use these sponges on my fry grow out tanks either air driven or as prefilter to HOB