Looking for Tube End/Dust Cap

Hi,

Does anyone know of a source for solid (non shower cap style) tube end caps?

Thanks,
Dave

I'm using plastic pail lids with a knob attached in the center (fender washers re-enforce this attachment point), they slip into the tube. Paint cans, dry-wall paste, etc come in various sizes and have flexible sealing edges. I got mine for free at a construction site and peeled the material residue off them. Also plastic tupperware style covers in kitchen supplies sections of dept. stores provide a snap-on fit if you find the correct size, I'm using one of these as well. Ron