This looks really lovely Tim - we've just taken delivery of our Cane furniture for our one...........you are so right about it being expensive!
Do you mean blinds for the ceiling or windows? We might look into some blinds next summer, only our conservatory has a glass ceiling (it was custome built onto the house 10 years ago at the time the house was built) and the roof is extremely high and sloping - but all glass. My BIL has just had some made for his conservatory and the window ones cost just over £600 but the ceiling ones cost just under £2000!!!!!
Pricey, very pricey!