Henry,
I think you're going to be a whole lot happier with NetBSD or OpenBSD on 32-bit Sun
SPARC hardware than trying to coax SunOS into a usable state for the modern, unfortunately
rather hostile, Internet.
However, I think you're also going to want to make use of the cross-compilation tools
provided, i.e., build software on [ugh] fast x86 or ARM hardware rather than wait for the
old SPARCs to grind through it.
I hope you have cheap electic power service where you are - old Suns run warm and use a
lot more electricity per cycle than modern processors.
The other way: emulation on modern power-efficient hardware, e.g., with qemu.
Erik