Yeah, no wonder - what's the MSRP of a 1070TI? $450-$500 IIRC?
https://pcpartpicker.com/product/Nsbkcf/zotac-geforce-gtx-1070-ti-8gb-amp-extreme-video-card-zt-p10710b-10p
So, the cards that were <$500 have sold out.
You can spend another $100 if you want, with OutletPC and Newegg marketplace sellers gouging people.
Then it becomes a matter of justification.
If you'll spend $550 or so on a 1070TI, a 1080 is only $580.
https://www.newegg.com/Product/Product.aspx?Item=N82E16814127943&ignorebbr=1&nm_mc=AFC-C8Junction&cm_mmc=AFC-C8Junction-PCPartPicker,%20LLC-_-na-_-na-_-na&cm_sp=&AID=10446076&PID=3938566&SID=
Then looking up to a 1080TI you're another +$170 for reference:
https://pcpartpicker.com/product/f2p323/evga-geforce-gtx-1080-ti-11gb-gaming-video-card-11g-p4-5390-kr
Or you're at $800 for a liquid cooled offering from Corsair
https://pcpartpicker.com/product/8ws8TW/corsair-geforce-gtx-1080-ti-11gb-hydro-video-card-cb-9060011-ww
*****
I'd just pick up a standard 1070 for nearer $450 *IF* I had to buy something right now.
https://www.newegg.com/Product/Product.aspx?Item=N82E16814127947&ignorebbr=1&nm_mc=AFC-C8Junction&cm_mmc=AFC-C8Junction-PCPartPicker,%20LLC-_-na-_-na-_-na&cm_sp=&AID=10446076&PID=3938566&SID=
Otherwise, wait.