So sorry to hear of the mishap with your C1000 Typhoon, that's a real shame
I have the C1000 Cockpit edition and its a lovely watch, so I feel your pain.
If you are not able to get a replacement case from CW, (and that is a real shame), I think the chances of finding a correct CW C1000 replacement case only on ebay are slim to non-existent I'd say. - You might find a defective/non working C1000 (maybe water damage or something?) to use for the case parts, but again I fear the chances are pretty slim, since replacement ETA 7750 movements/parts to fix one are readily available, but you never know....
The other two viable options as I see it (and as mentioned previously) are, (in no particular order):
1. get a generic PVD black St. Steel case and transfer the movement and dial over - this is very easy for a competent watch maker, (not one of those guys that replaces batteries in a shoe repair place!
), but you would need to know the EXACT dimensions for the dial diameter/opening (easy enough) and whether CW have fitted a movement ring and the diameter, (rather than securing the movement in with standard case clamps), again another critical case dimension for the case. - From memory
, (I don;t have mine in front of me), I suspect the former as the dia of the visible dial is larger than the dia of an ETA 7750 movement......don't quote me on that though, as I say ......from memory. - Ideally you'd want CW to source and fit the 'generic' (or CW ETA 7750) case for you as this way you may still have some balance of warranty after.
The downside of this is that you don't have that beautiful engraved Eurofighter on the case back (it won't fit on to a generic case), but you would have a wearable watch again..
2. You repair it (or get it repaired for you), using some form of adhesive (ideally specialist ceramic adhesive?) - not an area of my expertise so suggest to do some research - the downside of this is that no matter how good a job is done, its likely that the repair will be visible to some extent - the upside is that you'd still have the original case and it should be fairly quick and cheap to repair. --- If you do go down this route, (and if you have no luck with finding a replacement case, then what have you got to loose?!), then I would recommend wearing it on a NATO or single piece pass-through strap, for the reason that if the lug does come un-glued, the watch head will be retained on the strap by the other spring bar and not fall to the floor.... plus you should be able to carefully fit the spring bars then
feed the strap through, rather than putting undue stress on the glued lug with a spring bar tool + strap.
Might also be worth getting in touch with CW again (unless you have exhausted this avenue) in a few weeks time after the busy sales period (plus the service/repair dept is closed due to Covid at the moment).
I hope that helps a little, and I hope you manage to get it fixed so that you can enjoy wearing it again..... (in the mean-time you have a desk chrono?!
all the very best of luck with it, and please do let us know how you get on.