Takealot - Incorrect item sent, instead of replacing they want to give credit or refund

Items I ordered took just over ten days to arrive, and when it did it was the incorrect size( basically half the size of what was ordered. I logged a return request with the preferred outcome to be to have the items replaced with the correct ones. I wanted to use these items in a solar dehydrator that I had already build to the dimensions of the items ordered. So now I have spent a sum of money and quite a bit of my time just to be told they dont have the correct items in stock and want to credit my account. This does not compensate me for the time lost, cost of shipping should I source these from them or elsewhere or the time and effort to rebuild my dehydrator if I cant find items that fit the spec of the previous product.

I also note from the comments made on the product listing that I am not the first person they have sent the smaller items to.