Light Collapsible

General price of sundries?

I’m planning to take just a few necessities for a no-frills, tight-budget trip to London. (Taking one carry-on backpack, for a length of a one-week stay)

Can you give me approximate prices of items listed below?
Pounds are fine, I can do the math into dollars.
Thank you!

Toothpaste
Shampoo/Conditioner
2 AA batteries
bar of soap
1 [...]