[oletrucks] vacuum advance

[Brad Newman <bkn6@airmail.net>]

Can anyone recommend a source (other than Chevy Duty) for a vacuum
advance for a 216? I have gone through 3 different ones (all new) in the
last 7 weeks. All 3 have come from Chevy Duty, and all have been made in
Taiwan. None of the local auto parts stores around here (Dallas) carry
them, and frustration is starting to set in.
Will one from a 235/230/261/292 etc fit? Maybe I would have better luck
if I broadened my search parameters. Any suggestions?
Thanks
Brad
49 3100 (running rougher than a cob)
24 1 ton