It is far milder than most other livestock diseases. But it is highly contagious. It is similar to the flu in humans as far as how dangerous it is. One of the biggest problems is that animals can recover from FMD quickly and then not be recognised as carriers. Animals shed virus days before you can see symptoms.
Cattle shed huge amounts.
The US has large stocks which could be used along with the Pirbright and EU stocks. Commercial companies can make them too. Vaccinations work equally well in all species and there are no special problems with sheep or pigs. As evidence they had been eaten and their products such as milk drunk without any adverse effects for 40 years in the UK before the ban on vaccination started in the early 90's. Plus we already vaccinate for MANY other things.