Having had the odd bit of experience with the film industry, it is true that many situations happen in real time, director decides a different angle is needed, or the envisaged shot doesn't work and so on. However, if it involves background artists, cars, trucks, motorbikes, or even buildings it is doable (most times), but in this case for the producers to either not have pre-planned said B707 into their shooting schedule way ahead of time or realise that said aircraft type is as rare as a hen's tooth these days, or for that matter last 20 years is plane
and simple bad business planning, especially considering the costs involved in film/TV production.
Realistic options ? 1) CGI mixed with museum steeds 2) Omega Air 3) USAF KC-135 4) N88ZL if not sold and with up to date airworthiness.
SHJ