Yeah - I'd recommend switching to the internal system. If Vectorworks can supply the mast base, the rest is off-the-shelf parts (although I think there may be some spacers on the top bolt).

Putting it together will be a bit fiddly, but really not that hard. When I took mine apart, I successfully taped a bit of rope to the end of that top bolt, pulled the bolt out, and then lowered everything down the mast. Reassembly was just a matter of pulling the rope tight, and then sliding the bolt back through.

Initial assembly will be a little bit harder as you'll need to put stuff onto the middle bit of the rope whilst it's hanging out the bottom of the mast, but if you use sufficiently thin rope, you should be able to cut and knot it, and still get it through the bolt holes in the mast.

Paul