Don't know the composition or set up of your current one. Nor am I a professional seamstress so I can't be of much help on that matter.
However there are wallet and cellphone pouches. You can definitely find them on amazon. Other stores such as Marshal definitely has belt pouches for cellphones. But for wallets, might be more tricky to find in store.
When in doubt, just take the next small step.
With that next step take a deep breath. It calms the mind.
When the mind is calm you realize the best is still yet to come.