Felix, make sure you check betul-betul the vet punyer pengalaman dalam membuat surgery, because many vets though qualified do not have good and long hands-on experience in doing surgery. That is why there are so many qualified vets offering even free neutering services to rescuers simply to acquire this precious experience.
Make sure you go to his/her clinic several times when he has done the surgery on other people's cats to check the wound to see for yourself how neatly it is done. I have seen horrendous cases. Potong besar, jahitan tercabut, get infected ... how the cats suffer at clumsy and incompetent hands walaupun the vet is so called qualified (but not every one is a good competent surgeon).
Good luck, dear and happy for Blackie!