Make your own? We homebrewers are good at that kind of stuff. My thoughts for a quick and dirty version are.
Bath tub. Filled with water of the appropriate temperature (maybe salted for bouyency). Make a box, insulate the hell out of it with sound deadening foam, make a couple air channels, have them go around several turns with same sound deadening materials surrounding. Place box contraption over bath tub, trip
Bath tub. Filled with water of the appropriate temperature (maybe salted for bouyency). Make a box, insulate the hell out of it with sound deadening foam, make a couple air channels, have them go around several turns with same sound deadening materials surrounding. Place box contraption over bath tub, trip