Lost Part

I have managed to lose one of the black lugs from my Aquaroll (the bit that the handle fits into). It must have dropped off the barrel whilst on site. I contacted my dealer who suggested that I get in touch with the manufacturer. Royal Leisure were not the least bit interested in helping me and just insisted that it was part of the barrel and couldn't be supplied as a spare (I will be avoiding their products going forwards).

Does anyone know where I could get one from to avoid having to but a complete Aquaroll?

Thanks

Steve