Most of these, if not all, are in the wrong scale, i.e. they are not 1/72/6, but they are free. If you don't have a 3D printer, there are quite a few people who will print them for you. I would use a resin printer for these rather than a FDM type so that you don't get a bunch of annoying lines.
Large collection of various vehicles at 1/200 scale: https://www.thingiverse.com/thing:3555618
Large collection that includes a Renault FT75BS and a Fiat 3000: https://www.thingiverse.com/thing:2413246
