So, just a followup Post to say that I was able to contact Essdub (aka Graham) who provided a complete manual conversion kit for my 2000 5sp Spyder. Excellent price, excellent service!
I'm not a trained mechanic, but have access to a workshop.. and have done a bit of work on various cars over the past few years, including a full engine rebuild on the Spyder with some warm up parts. The manual conversion parts arrived, and a number of weekends later, including a few emails and calls to Graham, and also a remote computer session for Graham to diagnose a problem with the new manual ECU and immobilizer using techstream and... I have a manual Spyder!
This conversion has given the car a new lease on life... it is quicker, more responsive, more controllable, like having a brand new toy.
If you have an SMT (which I guess most of us in AU would have had....) and want to make the car come alive, or just solve an issue with the aging SMT components, make sure you get in contact with ESSDUB
Cheers,
Todd.