I have just finished a piece for Sarah at the Deux Sevres Monthly, where I talked about sourcing ingredients for Christmas cake, pudding and mincemeat.
One of the problems that James found out is that suet is not really a commercial product here - it is the hardened fat around the pig's kidneys that our Grandmothers used to buy and chop up for use in their kitchens.
The solutions I offered was to go for a vegetarian option for Christmas pud and mincemeat, and here are the links below for the recipes that do not require any addition fo suet.
Vegetarian Christmas Pudding by Roopa Gulati
Vegetarian Mincemeat by Rose Elliot