Credit to Davbar24 for this now sold out deal, while looking I found this one too.
It gave me an additional 20% off coupon from Amazon for me bringing it to $45.67 which is as round as Santa's tummy, but this could have been unique to me.
Delivery by Christmas according to Jeff Santa Bezos.
Reports on the original post attested to the quality of their inflatables, pretty sure this one will also sell out quicker than marked down prawns on Christmas Eve so click now and think later.
EDIT
I took out reference to the discount in the title, suspect it was just for me as I made about 8 orders in a day and signed up for Prime. It wasn't a code, just a box to tick offering a further 20% off.
Thanks OP, I wish it was more chrismassy inflatable.