If I was you, I would buy an ANVIS MOD-3 pod. You can have your tube and optics installed in a pod and use it as a monocular. As you get more money later you can buy another tube, pod, and bridge and complete the goggle. A few dealers can help you do this, I used Ed Wilcox and I'd highly recommend him. There are also a few other AB night vision produced housings that are just monoculars that can take your ANVIS glass if you want to make a more functional device.
Your tube is a Gen 3, non-gated FOM 1600 limited tube. It shouldn't be too hard to find something that could work as its mate in a goggle. FOM 1600 tubes are actually pretty good tubes, a potential resolution of 64 lp/mm and up to 25 SNR is better than a lot of what is on the secondary market. The current tubes the US Gov is buying (OMNI VIII) minimum specs are a FOM of 1600.