Petes pilots, ( on ebay) uses soemthing like :"expanded latex" I think he calls it, he posts the weights with each pilot as I recall.
I have been very happy with them, though you do need to REALLY clean them before painting. The mold release some times is dastardly difficult to get off, and latex paints do not like it at all.
Rudy,
watching for an email,, nothing yet?