It really looks like the SC-8000 driver should work with the SC-7000 as they should bot share the same ASC-9408a / DSP9410A chips.
See here:
SC8500 sound card - what does it do?
Here is the really old page from the web archive AND the driver downloads work. Looks like the ASC-9408a is WSS compatible.
The 66w95drv.zip should work for you in Windows. Look at the Readme. You will want to select "Windows Sound System and MPU-401, Wavetable Synth".
https://web.archive.org/web/19970127055743/ht … ww/drivers.html
There is also a real mode DOS WSS driver - not sure if this will work or not.
Microsoft Windows Sound system ISA Drivers help.
Also.. from other information I have found, the SC range of sound cards were also abbreviated to only two digits.. so yours would be SC-70.
Edit: Information from Gallant specifically saying this... and the drivers again on their newer site even though some of the drivers are no longer there:
https://web.archive.org/web/19971018190128/ht … ww/scdriver.htm
Newer download page with most of the drivers for the older cards - but not downloadable:
https://web.archive.org/web/19980121044954/ht … ww/scdriver.htm
/Edit
Edit 2: The Terratec Meastro 16 drivers might work as well.
http://terratec.ultron.info/Audio/Maestro/16/Driver/