We're replacing our master bath tub, and I'm having trouble finding "the" tub.

I can find a tub that will work. The problem is that we would like to upgrade to acrylic, and steer clear of FRP.

The installation type is 3-wall alcove. We need an integral tiling flange, and would like an integral apron (see below).

So far, so good. The trouble begins with the tub size and drain location. The rough opening is 60"x48" . The old center-drain tub - a Corlglas if anyone remembers that brand name - completely fills the 60" and nearly all of the 48" . This is a concrete slab foundation, so moving the rough drain is not an option.

We'd be okay with somewhat less width, and indeed 60"x42" seems to be a common size, but they are all FRP (Kohler, Lasco).

There seems to be more choice in acrylic for right and left hand drain tubs, and frankly a right-hand drain makes more sense for this installation, but the rough-in is the problem. One idea I had was to let go of the integral apron idea, and install a right-hand tub without apron above-floor, piping the drain over to the rough-in, but the wife is really stuck on that integral apron, at least for now.

I've spent hours on the websites of all the tub manufacturers I can find - Lasco, Kohler, American Standard, Americh, Acryline, Toto, etc. but I can not find the right tub. If anyone has any ideas, I'd appreciate hearing them.