Looks like you may either have to buy by the metre and add curtain tape etc or have them made to size as your window is not a standard size. That is as far as I can see, happy to be corrected.One example here. http://www.terrysfabrics.co.uk/prod/curtain-fabrics/lining-interlinings/54-wide-curtain-lining-cream/
I know someone who made blackout curtains for the South Foreland lighthouse, but you have to purchase the material from specialist manufacturers, then make them yourself.
Thanks everybody. I've tried all the suggested sites, but no-one seems to make the linings in 60" drop. I may just have to buy the 72" ones and lop quite a bit off the bottom! I don't really fancy making them from scratch.
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