Here is the P65 I was telling you about needing a plastic gas-line fitting for on the carb.
In reviewing the two links below they sure appear to be of the same lineage!?? The Poulan 655 is a re-badge of the Pioneer P65??
Model Profile: P65
Model Profile: 655
If you can't find a new barb consider buying a brass plumbing barb and either turn it down in a lathe or chuck it in a drill press or electric drill and file one end down to make a press fit in the carb.