How can I change the original price on OpenCart product page?

Question

Without using the Admin panel. I want to be able to change the price of an item in OpenCart on the product page.

Basically I have an Option called Bespoke/Custom:<

Answer 1

-"This should only point You to the right direction (while believing the finish is not that far). via @shadyyx"

Thank you @shadyyx - for showing the correct approach... I managed to get it working and this is how:

if(isset($this->session->data['cart']['custom_price'][$key])) {
    $this->data[$key]['price'] = $this->session->data['cart']['custom_price'][$key];
} 

should be :

if(isset($this->session->data['custom_price'][$key])) {
    $this->data[$key]['price'] = $this->session->data['custom_price'][$key];
}

Thank you again and I hope somebody find this useful.