The coil isn't a permanent item. I would encourage you to consider it more like a service item. I changed an old decrepit coil and got 20 miles more out of each fill-up!

The peg coil is positioned in a real horror show of a position, it gets a healthy spray of road crud, probably being positioned there so it remains cool.

The spade terminals just underneath the plastic of the coil housing are the place which corrodes first. if your spades appear to be wobbly, then they are bending at the corrosion and will soon be breaking.

https://www.apriliaforum.com/forums/showthread.php?285121-Busted-off-coil&highlight=coil+nailed 

This thread tells you how you can 'nail' the coil in an emergency (I rain a nailed coil for about 3 years!).

There is also a little coil hat on there which is useful to keep the weather off the coil.

Yam manual gives full diagnostics on the coil, if it is out of the specs then it needs changing.

There are many coils which will do the job, 2 terminals and 80mm between holding bolts. However, you need to ensure it is an external coil (weatherproof) not an internal one (won't last long in moderate rain.... I know)

(CUrrently struggling to find a link to a compatible item but I will keep looking)