Check out cameras that go up to about £100 or more as their basic price from big names like Canon, nikon, samsung, panasonic, Fuji, Sony and ricoh.
Then sit tight and watch them - sign up for emails from people like jessops, amazon, warehouse express (wex), London camera exchange (lce) as well as tesco, asda, john lewis, argos, boots etc (I've probably missed some) and then wait for the pre- Christmas offers.
In amost all cases they had reasonable £100+ cameras that dropped by at least 50% or more. Black Friday week on amazon had some amazing deals on these sort of cameras - along with other shops joining in for similar such deals.
If you can string it out that long you can get a much better camera for your money that will last your ds much longer too.
Also other random things to consider:
Better to spend £50 and get a £100 camera than get a £50 for half price.
Avoid the digital cameras that just cost £20-30
If you (or your dh) already have a compact camera, consider getting one that's the same make as you might find you can double up on battery chargers etc plus even if the controls aren't identical there's a better chance that it will be a lot more similar than other cameras from different brands so you will find it easier to use/explain (not a given but at least worth thinking about!)
You'll need to make sure he has a case for his camera and a couple of memory cards - play and 7dayshop often have good deals. A little special lens cleaning cloth is a good idea too.
Make sure the camera doesn't have AA batteries to power it - it will cost you a fortune in batteries! Rechargeable battery that comes with the camera all the way.
Think of getting him a box or basket (not a sealed one though) or dedicating a part of a shelf or drawer etc for all his camera bits and bobs so that he will always know where things are - it's easy for them to put them down, get distracted and forget! Plus if you find it you will always be able to put it somewhere safe. Getting a 'big boy' equals big boy looking after (and easier to train when linked to first exciting gadget!)
Dpreview.com is a great review site for cameras but there are others out there too.
Argos (and probably others) have clearance shops on eBay. You can find some great deals on them - and often at this time of year as they are clearing out old models to make way for new stuff for Christmas. Digital cameras these days are pretty good, and especially at this price point, you're often better off getting a real bargain on a higher spec camera from last year than paying a premium just for the sake of it being new. If you look at lots of camera prices on camelcamelcamel