Hello,
Converting SD to HD is basically not possible. All one can do is to clean the noise, recolour, make the final image look sharper, and of course increase the number of pixels to get a larger image. If you like you can send me your file and I can process it in after effects doing denoise, .... then if you are happy with the result you can pay me. I will do the work only on a small piece for now. Please message me if interested. Thanks.