UK Tax Questions? Ask a UK Tax Advisor for answers ASAP
Thanks for your question - I am Sam and I am one of the UK tax experts on Just Answer
I am afraid the Unilever website only goes back as far as 1999 - which is no good as you need the rebasing value rather than the purchase value to calculate your capital gain position.
All I can advsie is that you call the head office 01372 945001 to see if they can provide you (or direct you to) with details of the appropriate value