As a Brit I was rather disappointed when I couldn't find this at all on MCPEDL so I made it myself. Unfortunately you cannot reverse money crafts, and the money items have no singleplayer value, they are meant to be a form of trading token to replace diamonds. You will be able to find the exact recipes in survival mode, and they shouldn't be muddled around at all, for example making a sword diagonally. However, all coins and notes can be created without a crafting table, in a 4x4 grid. All recipes are designed to be the most efficient. The ingredients are:
1p: x1 Copper Ingot + x1 Raw copper
2p: x2 1p
5p: x2 2p + x1 1p + x1 Iron Nugget
10p: x2 5p
20p: x2 10p
50p: x2 20p + x1 10p
£1: x2 50p + x1 Gold Nugget
£2: x2 £1
£5: x2 £2 + x1 £1 + x1 Paper
£10: x2 £5
£20: x2 £10
£50: x2 £20 + x1 £10
You can also give yourself these, with the prefix gbp: instead of minecraft:dirt for example. Unfortunately the textures are flipped/mirrored because that's how minecraft works, and I am unaware of a fix. Items in 3rd person looking down from above will appear correct though. Additionally, the £2 coin in this add on is a rare end of WW2 coin, because I couldn't get a great shot of the original £2 myself.
I had a lot of fun making this money add on, and I hope you enjoy these coins and notes as much as I do! Happy trading!