You can get travel insurance from Insure for all (http://www.insureforall.com/) who specialise in providing travel insurance for those aged 65 and above. They have won awards for the cover and service they provide.
I did a quote for you based on a trip for 15 days in Europe and it comes up to £36.49 (worldwide is £104.99). Visit the site for more information or if you prefer you can speak to them directly on 0845 8800694.
You arent grounded at 75

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