I love my books so I feel for you - I had babies tear board books, even this week and I just patch them up until they can't be fixed and then I recycle them then I get another batch from my 2nd hand books store or where ever I find them
also if you are into buying books from Scholastic as I do for your daycare they have special end of the school year in June so you could apply now and buy them cheaper than other times
I keep my circle time books away from kids and just give them the older books