pruning poles

[Neill, Amanda]

Dear all,
  I am looking for a source of the good, old-fashioned, aluminum pruning
poles, each 1.75 m long, with male and female nesting poles (sold in sets of
two), connected by pins/pegs that fit into holes at the junctions.  We have
the clipper head, but a source for these poles cannot be found.
  Missouri Botanical Garden used to sell these, but they no longer do!  Any
source, world-wide, would be helpful.
Thank you,
Amanda Neill