Check out this link for the drivers:

http://www.markyb.org/farallon-ethermac-se-driver-disk-version-2-2-1/

I've found that the Farallon EN install works for the majority of that era Farallon network hardware, including the etherwave. I've managed to get TCP/IP working on 7.1.1 and 7.5.3 - but it seems dependent on working PRAM. The driver will install an "Alternate Ethernet" adapter, use that for IP networking.

Hope it works!

Alex