Transco have snagged the boiler Flamingo 50 as unsafe?

Transco have snagged the boiler Potterton, Flamingo 50 due to Flue Terminal being incorrect. The Aluminium box is there(14"x 12")but there is no mesh around and in front of the hole to stop the birds rats etc from going in. It has been classified as 'Unsafe to use'. Please advise if necessay parts are available at your facility and at what price.