The only thing I would salvage personally looking at that is any storage drives you have (not the OS drive). The thing is that really important components are so cheap these days for brand new that I think you would just be doing yourself a disservice not doing that. Even the case, I would just get a new one unless you love that one and it has USB 3.0/C etc. to keep you going for a bunch more years.
I have a Rift S and I love it. It's not that hard to run (my 1080Ti handles max settings on every game easily so far), and I've played what I think are all the popular titles and I have literally not once noticed it missing one of my inputs - the tracking is insane, I don't know how they make it so precise. Based on my experience and ease of support, I would recommend that headset. None of the current VR headsets have even close to high enough resolution for a truly immersive experience, so you might as well just get what works well, is well supported, and your PC can easily run. Not having to set up beacons, use a million USB ports, run cables everywhere, and dedicate an entire room to VR is probably the single biggest perk of the Rift S IMHO. Just my $0.02 there.
As already mentioned, your biggest single cost is probably going to be the GPU. You need to decide if you want to try and "future proof" yourself now with a beastly card, or get something more modest and then upgrade only if necessary down the road (probably what I would do).
Here's what I would buy if I had to go out and buy a budget/bang for the buck VR Rig tomorrow:
https://ca.pcpartpicker.com/list/BtjW4n
I assumed you will use your own storage drives, your old case, and will use a $10 eBay Windows Key or similar solution.
If you want to spend more: Change CPU to 3800X, change GPU to RTX 2070 Super, 1TB OS drive (if you need the space), bump PSU to 750-850W if upgrading CPU/GPU or doing a big OC.
EVGA's G3 PSUs based on the SuperFlower Leadex II platform are arguably the best in the industry, and the 10 year no-hassle warranty is a bonus. I'd go EVGA too for the GPU because their warranty/support is second to none.
CPU comes with it's own fan that is actually pretty good - if you want to OC, you will probably want a better one.
Black Friday typically is nothing special at all for PC components other than maybe a slightly cheaper SSD/HDD.