The BBC is offering DVDs of its classic drama productions "from £7.99". The BBC shop’s website is featuring the "old" Pride and Prejudice (Andrew Davies/Colin Firth version) for £11.99 — it is twice as long or more than the current (Deborah Moggach/Keira Knightley) version, and although it contains a few Andrew Davies-isms deviating from the book, it is a wonderful production.
Persuasion is £9.99, Wuthering Heights £7.99, North and South £9.99 and many others are listed. I can recommend the North and South (starring, as Cathy tells me, "Guy of Gisborne"), but have not seen this version of WH. I have seen a good ITV production which covers the whole story and not just the first half, but I trust the BBC to do the same and not go the Hollywood route of missing out all of part 2. The ITV version, incidentally, features the current Mr Darcy, Matthew MacFaddyn, in an earlyish role as Hareton Earnshaw.
It is probably worth doing a price comparison on Amazon, but the BBC’s listing is a quick way to see what classics are currently available, which Amazon does not do so well. (Amazon’s definition of "classic" being unintentionally amusing, when you see some of the titles interspersed with those that would be more generally considered to be qualifiers.)