I'd recommend that you do not try to develop for a platform you cannot test on.
This is a recipe for a long, slow, and confusing development process, and a poor result with terrible experience for your players. You have so many other options for target platforms — with vastly greater market share — I don't see any good reason to put yourself in this position.
That said, since Unity is a cross-platform engine that can package games for both mobile and PC, you could as TomTsagk mentioned get yourself a Google Cardboard to test your VR experience with your phone, then compile for Oculus/PC and hope it behaves similarly.
I'd recommend you at the very least recruit some testers (working remotely) who do have the actual hardware, and can test your Oculus builds and send you feedback. This likely means a day or more turnaround to find out whether your bug fix worked, so it's not a good way to make high-quality games (or enjoy your job). But if you're dead set on developing for VR without the necessary tools then I think this is the closest you can get.