I have an HP LaserJet 4100n with duplexer and C8053B envelope feeder.

The envelope feeder will pull the bottom envelope into the feeder an inch or so, but fails to make the final draw of the envelope into the printer.

I've replaced all the printer's rollers. If this is an issue of rollers in the feeder, I read in an old thread here that getting replacement rollers for the C8053B may be a problem, but "refurbished" feeders are being offered. If truly refurbished, new rollers are out there, somewhere.

I removed the bottom of the C8053B to look for anything obvious, even to this layman, and nothing caught my eye. What is the likely fix, and which supplier for C8053B parts is reliable?