Eames knockoff- Help with plycraft/selig swivel mechanism  

I own and have restored a plycraft lounge,
and recently bought a heavier selig version,
with a wobbly base. After searching this
forum, going to the abacus swivel parts
website, and general research, i am confused.
The parts website recommends either part
402 or 502...but neither of those have a
threaded post like mine. The post comes
free from both base and swivel tilt mechanism.
A post on another forum, modern hippie,
recommends part 11p or 24p. After emailing
pics to swivel chair parts directly,
they said...
"Rather than a Lounge chair, it is an
adjustable height chair which can be
used as an office chair.
You can replace the mechanism with our
#475 size 15 ½ Use a hack saw to cut
to length. Pay strict attention to the
pivot pin!"
SO NOW THERE ARE THREE answers to my
question! I have attempted to include
a link to a photobucket album with
pics.I CANT BE THE ONLY PERSON TO
HAVE THIS QUESTION! HELP!!!
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