There are lower-cost off-brand alternative Fresnel boxes, such as this one, but I'm not prepared to vouch for any of them. It's not that the optics are critical or anything of that nature; Fresnels are kind of sloppy in any case. It's more to do with cooling, especially when you're using modelling lights. Unlike (most) softboxes, Fresnel boxes are pretty small, so the air inside can heat up rapidly when you're using modelling lights, operating at high power quickly, or both. (And the Profotos aren't that bad, if you compare them to, say, the Broncolor Flooter.) To be clear: I'm not saying they're bad or dangerous. They may be perfectly fine. I'm just not prepared to state for the record that they throw good light and won't lead to overheating problems.

Thing is, though, you really just want the quality of light that a Fresnel gives you, not necessarily a Fresnel unit per se. And you can get close enough for jazz with a gridded reflector of the right kind. If you're a Profoto user, I would suspect that you can get pretty much the effect you want using a Magnum with grid and barndoors or a Telezoom. For closer-in applications where you want a large soft-ish spot and quick fall-off (the classic Hollywood look), you might find that a small gridded beauty dish will get you where you want to go.

If you're shooting slow and modelling lights are not a worry, you can easily jury-rig a small Fresnel using a resin lens from Edmunds Optics. If you can find an old tungsten or arc Fresnel unit, you can probably have it altered easily enough and get a more authentic wide-ring Fresnel look, or simply use the lens. You simply need nested boxes and a way to adjust them, and you can cannibalize a third-party speed ring as a flash mount.