I got a couple of different kinds
Scintilla fly buoy foam 2 mm thin #15 Creme
Rainy's cross link foam cream 1/16 "

Also I have the hareline dubbin micro thin foam in tan which is not qute cream but not so far away which i was going to try but haven't as yet.

In the end I used the Scintilla which is a nice colour and at 2mm fairly thin but still seemed a little thick for the pattern, although perhaps there are ways to make them a little thinner. The patterns looked really cool until i actually had a real mayfly in my hand in the UK (the same river as in the DVD from Oliver edwards) when the abdomen was definitely too fat in my version.

All these came from Marriotts, I live about 30 mins away so get to peruse at my hearts content. All of them were fairly cheap ranging from $1 to $1.65.

They're usually pretty helpful so give them a call or order online.

David