wwwaaaaaaiiiiitttt! dont buy a pump yet!
Hi. My disco V8 had a very similar (if not exact) problem. It would occasionally cough and splutter accompanied by great loss of power while I was driving but more often than not would idle poorly every now and then accompanied by an engine stall or very close to....
I tried everything except fuel as I beleived it was electrical. I mucked around with dizzys, rotors, plugs the lot. The problem was it would do it only every now and then so was hard to diagnose. Eventually after all these changes, it started to do it again!!! I eventually thought bugger it and replaced the coil (against all the advise from freinds who beleived it was fuel related) and presto!!!! I now have a beautifly fuel efficient (ha ha... well more efficient), smooth reliable v8 that no longer does this intermittent wobbly gasp!
Cost me $145 for the coil. I hope this helps