If you process it and the film sez Scala on the edges, and it is higher in contrast than you expected (processed as a neg), then it is probably Scala.
I would try one roll rated at EI 100. Shoot it in flat light, and develop it for 5 or 6 minutes in something like D-76 1:1 or HC-110 dil B. See what you get. If it lacks edge marking, it still could be Scala. Sometimes relabelled film does not have edge markings. If it is low in contrast, it probably is not Scala.
I would have no reason to doubt B&H's claim, however.
Good luck. It is a great film if used for the right things.
I find that this film's best use is as a very high contrast negative film to be used in very flat light. Most recently, two 120 rolls of it that I have had for years (waiting for the right conditions) turned some very dull shots of mine shot in the Smokey Mountains in winter into beautiful, contrasty, sharp pictures without having to overdevelop the film, like I would have had to have done with FP4, Delta, etc.
If all you want is a black and white transparency film, you can use any normal b/w film developed to higher than normal contrast. Ilford has a published reversal process, and so do some other folks. You can also send it to DR5 lab in Colorado, U.S.A., and they can do it for you.
There was nothing special about Scala that made it a transparency film specifically. It was simply a negative film built with contrast characteristics that were well suited to reversal processing.