BitPay has a module for prestashop. However you need to verify your real name/addresses with your documents. Their site: https://bitpay.com/bitcoin-for-ecommerce
They also accept converting and sending the money to your bank account automatically.

Here is an alternative: https://www.prestashop.com/forums/topic/123451-module-free-bitcoin/
These modules are free.

If you have the money I would recommend you to buy this: http://addons.prestashop.com/en/payments-gateways-prestashop-modules/13804-blockchain-bitcoin-payments.html