Does anyone know what the cost might be for a post mortem .
Thank you

Only your vet can tell you that, I'm afraid.

I think it will vary a lot depending on whether the vet merely conducts an examination of the body or slides and samples are examined for pathology perhaps by a specialist laboratory.

A general autopsy is £250.00 for a medium size dog more in depth tests on tissue,organs and fluid but not blood as they dont test blood as to why is beyond me but anyway that will be extra. If your looking to take this further say with RCVS save your money and heart ache as its a no-win situation and they drag it out for at least three months and fob you off left , right and centre.
On the other hand dont mean to sound so heartless and you are obviously suffering at this moment in time but most autopsy's prove to be inconclusive probably something to do with the fact that they are vet lab's that carry them out but if I had to do it again I guess I would