Yes, if absolute precision is needed, what he wants are pin-registered vacuum film holders. Linhof used to make them (or at least sold them with their name on them) they had a little battery powered vacuum pump. However, pin registration requires that 3 precision holes be punched into the film. Linhof also sold the punch to do that. Needless to say all that stuff was not cheap; on the other hand, if you could find them used, they probably would be cheap, who else would want them?
FWIW, my Graphic Riteway holders have a 96mm x 122mm opening, which is 5mm less than the nominal size of the 4x5 sheet of film.