starter motor replacement any ideas

[Kilg]

Mine always starts fine when cold and is also usually ok if I shut the engine off when warm and then restart straight away.

It only tends to happen when I've driven it for some time, turned it off and then tried to restart about 15min later. The last time was at a motorway services; For about 40min, every attempt was met with silence from the starter (trying with push button or with key made no difference). Then eventually I managed to get a few partial cranks of the engine before the starter would stop again. Finally it burst into life after about an hour of cursing and just as I was calling the breakdown service.

The only error code I have is:

19510 - Starter will not turn.
P3054 - 001 - Jammed or Electrical Malfunction - Intermittent

I had been assuming that it was just sticking when hot (particularly when it had been sat for a little while and had chance to heat soak from the engine/trans). I'm hoping it's something else though given the work involved to change it!