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HI. You have done the right thing. The net point of call is the Land Registry - they may be holding a copy of the lease as all leases of a certain age require registration. They are a very user friendly organisation and for a relatively low fee they may be able to supply a copy of the land title and lease. I can't promise anything but recommend a try. I trust that this has been helpful, do let me know if you have any other questions. Good luck.