'Tis LTS 5 indeed, from about 1996. Steel all round, came with Alivio and yellow RST forks to match the rear. I'm pretty sure the front triangle mounting is different to a more up-market LTS so you wouldn't be able to swap rear triangles.
Looks like elastomers from proflex. The interchangable black disc in the middle should be used to control "preload".
Callum over at rapid decent scotland offers aftermarket elastomers for a whole range of proflex bikes and at different springweights. Perhaps he can help you out. He just broke his arm or something too, so it means hes stuck in his office getting orders out quicker than normal.
tom y knowlege you cant retro fit another rear end onto the elastomer LTs as the rear end was different to all the other LTS frames. It might be worth a try but why bother when you could pick up a full frame for less than I have seen rear ends sell for individually.
Bens Cycles has these elastometers for sale still, keep it as it was ment to be.