I've been doing a bit more research here based on your responses - Weldwood Plastic Resin (by DAP) is a urea-formaldehyde plastic resin glue.
The impression I've gotten so far is that this is the brew that pretty much replaces resourcinol.

I spoke with the national Gorilla-Glue rep, and he said that Gorilla should theoretically do the job if I could get enough clamps on it when setting up, but also said that the ideal would be a two part urea-formaldehyde resin.

We have an outfit called 'Glue-Guru' here, and talking to their resident expert - his vote was for epoxy on grounds that the urea-formaldehyde isn't fully waterproof and will slowly creep if it's constantly damp with the joint in shear. Also because it will fill gaps in the joint without weakening the bond.

He recommended a pre-thickened epoxy sold here as 'Builders Glue' for ease of use:
http://www.crc.co.nz/Automotive-Adhesives--Sealants--Fillers-Epoxy-Glues/p1/Builders-Glue-i1ceb09b9-a54d-4181-a021-7f5e9496fcab-6914.htm

It should be a bit more widely stocked hopefully, and epoxy certainly sounds like the most robust solution so far. This could of course also be my chance to use up my supply of West System resin that's been hanging around for a while with the resin going slowly yellow..

Thanks for your replies - much appreciated.
Simeon

: Resorcinol glue now days is likely more expensive than epoxy and
: has similiar health risks. I'd just use epoxy.

: Plastic resin glue, if you can find it, will work and might be less
: expensive.

: Gorillia glue would take a huge number of clamps, resorcinol glue
: too for a piece that big. Require tight fit and clamping
: pressure.

: Bill H.