After searching unsuccessfully for a looonng time for a set of the
"Y" poles for the Westy Bigtop tent I own, I finally got up the
gumption to fabricate a set.  As it turns out, this was extremely
easy to do with some ready-made gazebo awning parts available
widely.

The gazebo parts are strong metal pipe connectors available in a
wide variety of configurations and angles.  They are made to use 3/4"
metal electrical conduit and have wing-nut set screws for securing
the conduit. The connectors are, unfortunately, made in China but
seem stout and welded fairly well.  They have a poor quality
aluminum colored paint finish that rubs off.  I essentially
fabricated an entire top framework and used only the OEM adjustable
legs from the tent pole set.  Even these would not be necessary as 
pre-measured and cut conduit would work for these also.

Parts:

4 angled connectors for the corners with one leg canted to form a 
peak.  $4.99 each

2 ridge pole connectors, angled to match peak formed by corner 
pieces.  $3.99 each

"sufficient" 3/4 inch steel electrical conduit @ $2.99 per 10 foot 
length.  4 - 5 foot sections are used to connect the ridge pole to 
each side pole.  the ridge pole and 2 side poles are made with 6+ 
foot lengths, I forget the exact measurement.  so, in *theory* once 
could get by with 5 - 10 foot lengths of conduit.  I won't detail the 
mistakes in cutting i made nor the amount extra i had to buy. :(

End-to-end connectors are available to allow any long section of
pole to be cut in half for easier storage.  They are $1.99 each and
i did not use any of these as the poles store well in the bed of the
Westy.

Cutting of the conduit is easily accomplished using a copper-pipe 
tubing cutter but plan on buying a new cutting wheel after doing the 
steel conduit.  The rotary cutter leaves a nice, burr-free edge with 
the flashing rolled inward.

I've camped 5 nights now in this tent and the poles have withstood high 
winds, pouring rain, and a good deal of sunshine :)  Setup is quick 
with the wingnut connectors and the poles in one piece configuration. 
 I think splitting the poles for easier storage would decrease their 
strength and increase setup hassles.

-dan