I got them off a trader on here who sells wheels, the name escapes me at the moment, so I'll look it up.
Pretty much every Italian car on aftermarket wheels will be on PCD correction bolts, as nobody bothers making 4/5x98 wheels for a limited market, when 4/5x100 are so mainstream.
A bolt with a eccentric washer is not in itself dangerous, you'll find them use all over the place on cars, suspension usually to allow camber correction. Where people fall foul is not having the correct centrebore/spigot ring. The wheel itself must be centred tight to the hub, you can't run say a 60mm centrebored wheel on a 57.2 (iirc?) VAG, as if it moves, then there's a chance you'll slip the wobble bolts too and you're in a whole world of pain.
These were 5x114.2 and as you can see, took a lot of abuse on track.
link to supplier