Ouch!
Yep, that would seem a very good price as I paid about $20 more for mine several years ago when money was worth quite a bit more. Of course, not regretting as I've gotten plenty of value out of mine in the ensuing years.
On the other hand, for most of our electric fired engines that only have a single heating element, these lesser options my prove even more economical, and are far easier to find space to store.
https://www.ebay.com/itm/155864120970?https://www.ebay.com/itm/386101233861?https://www.ebay.com/itm/166229771320?These are likely not the best prices you can find on these units as I didn't actually look around, but simply grabbed the link to the first ones I saw, and there are other styles of these smaller ones out there as well.
With that being said, the larger variac as is being shown by Gil in the first post, really is the Cat's Meow for this sort of thing, and they can handle about any power requirements that you can throw at them, like Jensen 50's even with their three heating elements, or multiple engines for that matter!