It definitely is.
The Belton Brick (which was designed by Brian Neunaber) actually uses three 3 PT2399 delay chips and has three short (and fixed) delay times to do the job of simulating spring reverb.
You can do all sorts of pre and post filtering and tone shaping, but the reverb itself is what it is, pre-delay and all.
I actually like Belton Brick reverbs for certain things, but Fairfield doesn't strike me as the kind of builder to do "their take" on that type of reverb. I'd be just as surprised to see a Tubescreamer variant from them. They tend to do their own, very esoteric and cool stuff.