Whatever you decide to do Derek, take extreme caution if trying to remove the main spring yourself, as Barry also states, it is not a job for a novice since the spring too easily can harm yourself or your surroundings. If you decide to use the machine teaching yourself how to service/repair a machine, Graham Barber (departed gramophone enthusiast and collector) have relaxed and detailed videos on Youtube showing how service a HMV portable (HMV 101).
If you had not been in Australia, I could possibly have been able to get you the machine pictured below for a good price, and it also seem to have many of the exact components needed to easily repair and update your machine, or actually the other way aroud, components from your machine could make this machine shine. The postage costs to Australia would never justify it though, but it still shows that everything can turn up for sale sooner or later, really.....
Good luck, and hope to see you active on our forum in the days/weeks/months to come
