Thanks, for your help,
I think i have found what I need, I now realise that the HPI F4.6, Ansmann .28 and force .28 are all the same just different heat sinks.
As far as I can see, there is no damage to any of the liner or the piston. There piston is still snug in the liner, but not siezed, there are no scores, scratches on the liner or piston. I think it is worth trying a new conrod, the engine was simple to strip, no problems, will give it a clean to ensure no other damage and order a new conrod.
Any other advise?