I have just been looking for some large hooks (as in bicycle hooks, ladder hooks, etc.) and using Google I found Value DIY:-
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seem to have pretty reasonable prices for the sort of bubble pack stuff you find in your local shop, plus a few things more that you might not find elsewhere. For example that have 100mm screw hooks, much bigger than I've found elsewhere.
I've placed an order, I wonder how long it will take to arrive.