Most of the poulan stuff uses .080 ID, .140 OD for the line with the fuel filter and 3/32 ID 3/16 OD for the other lines
I have the very same blower and have used it well for many years. The model is #358-797991 and the parts and schematic can be found here through Sears Parts.
http://www.searspartsdirect.com/par...47/1503120?pathTaken=&prst=0&shdMod=358797991
There is normally a 2 x 3 inch sticker some place on the housing. I have seen them fade and not be readable, I have also seen cases where the sticker was put in the box with the blower, and was never installed, which means it is gone. model number should start with a 358.
The instructions, model# and serial# are located on a decal on the top of the air cleaner cover underneath the top handle.