I don't believe it I work for a national builders merchant and about 2 months ago i threw away packs of these cos they were obsolete and no-one used them anymore. I have just done a quick search of our database and there's nothing there anymore, although they won't advertise them, if you want them badly it may be worth visiting a few serious building and plumbing merchants (not diy shops) and they may hand you a 10 year old pack with 10 layers of dust on and tell you to leave now!!
Alternatively if your tap is that old, which it sounds like, it may be worth getting a new one, they retail anything from �60 upwards.
Again, however, visit a dedicated builders merchant / plumbers merchant as if you buy them cheap off the internet or diy shop and need spares you have no chance. I lose count of how many customers come into my shop saying they bought a bathroom / tap / water feature off a discount store and then expect us just to be able to fix it!!!
Best of luck
BB X