It's been an absolute challenge getting hold of most of these sets since early December so if you're still after them and Amazon is your preferred seller then jump in now.
I've been using flubit on these sets and been getting good reductions so worth a try if you're happy to risk it going out of stock.
Sets priced as follows:-
The Cave: £19.98
The Farm: £25
The First Night: £39.99
The Ender Dragon: £59.97
The Mine: £89.99 (Limited to 14 in stock)