If you can't source all the ingredients on the original list, here's a listing of substitutes;

it's arranged as the original item, then the alternates, choose only one of the alternates;
IMPORTANT some ingredients CANNOT be substituted, I will mark those clearly.

Ingredient 1st substitute 2nd substitute 3rd substitute
Suet Vegetable suet

unsalted (U.S. = sweet) Butter

  
Muscat Tokay Port Dessert Wine
Guinness other dark beer any beer Milk
Breadcrumbs NO substitute    
Pear Apple    
Fresh Dates Dried Dates Prunes  
Almonds Pecans Walnuts  
Soft Dark Brown sugar Light Brown Sugar Any Sugar