I got DD a Minecraft plush toy in Tesco recently. I know I've seen various Minecraft figures in places like the Art and Hobby Shop (where you would find Lego characters etc) or a specialist bookshop or good magazine shop (that does lots of different types of magazines) might have something.
I found a mini slinky in the National Art Gallery last week (Ireland but decent science type places should have similar).
Would Lego or Disney or somewhere do something like a "magic flannel" for Minecraft, or another favourite character? The kind that are scrunched up tight and expand when put in water?
A festive bath bomb (Lush do fun ones) or a travel size of his favourite shower gel or something like that?
Things DD has liked in her stocking at that sort of age included:
Wooden spinning top
Cards for soccer (Match Attax?) as she was into those
Nice colouring pencils and fun rubbers
A "make your own picture" with a wizards theme (you transfer rub various things onto the background - it wasn't Harry Potter but was a Hallowe'en thing with a wizard theme that I picked up)
Marbles - different colours and sizes
Pack of cards (we love card games)
Bag of dice (we're always losing them so spares are handy)
Mini cars and trucks - Matchbox, Tonka, etc
Mini Lego figures and sets
There's always at least 1 book, and I think we started a second most years at about 7 - a reading book (fiction) and a non-fiction (Minecraft tricks, lego ideas, sailing training, a particular historical period, something of interest to her)
Cosy socks are always a hit - fluffy ones to wear indoors. But regular socks are good too in fun colours/patterns/favourite characters. Or really good hiking socks for cold days.