Unfortunately, yes it is. It already is in the US. Really though unless you are competing in tournaments you don't really need to be concerned. They aren't going to wrestle you down on to the tee box if you show up to your local club with one. The C.O.R. rating on them is too high (limit is .830). The good news is as long as it is in good shape you should be able to sell it to someone on eBay for probably close to what you paid for it if not a little more. Just list it as a 454 Unlimited and use the words "illegal" and "rare" and you'll sell it easily. Something like this: RARE King Cobra 454 Comp UNLIMITED "Illegal" Driver
The closest club to it will definitely be the Cobra Comp 454. You can get a conforming version of the exact same club quite readily. Just look for the one's which DON'T say 'unlimited' on them. You can check the R&A website ( www.randa.org )for full details on how the conforming and non-conforming versions are marked.