I've just received my first Parker 65! Rather than get something modern, I'd really like to rescue its original squeeze converter, whose sac has hardened. It adds a nice weight to the pen, the original sac capacity looks usefully large, and as converters go... it's really quite handsome! The corrosion in this photo has since cleaned up nicely. Ideally, I'd like to use a synthetic sac, as the way the converter is put together doesn't lend itself to repeated disassembly and reassembly. Which are the good and bad synthetic sac types again?Are there any with P51 sac (too fat for this converter) style channeling lines?Any UK sources?Very grateful for any advice offered. http://i773.photobucket.com/albums/yy19/flounder2009/Parker%20UK%20Squeeze%20Converter%20Resac/Parker%20UK%20Squeeze%20Converter.jpg