I was trawling Shapeways and did find some pretty suitable ones:
1.
BFG Pre-Heresy Strike Cruiser
Probably the nicest, most detailed, most setting-appropriate out there. And probably mentioned before.
2.
Clipper Fast Transport
Has the prow design we all know and love. Though no printed samples. Also, less detail than the first one. The designer also has a couple of other designs of smaller craft with the same aesthetic.
3.
Gothic Battleship
This one captures the "Gothic", quite literally. Has a few other similar designs, as well as ground-based stuff too. Designer's page has a LOT of other designs. The prow, perhaps, can be acquired from some other sculptors. (There's one done by a sculptor on Resin Addict called
Zeus Prows) Combined with the aforementioned prow, it'd be quite suitable I think:
