Wallmurals.ie offers the following payment options:

Stripe
Stripe is certified to the highest industry standards and has obtained regulatory licences around the world. Secure access with granular permissions, two-step authentication, and U2F keys.

Paypal:
PayPal allows you to pay online in absolute safety. You can use the funds available in your PayPal account to make the payment, or you can pay directly by credit card, even if you don't have a PayPal account.  With PayPal, you will only fill in your credit card information once, because the information is saved and perfectly secured on the PayPal server.