I have some 68881 20Mhz math coprocessors that are original Sun parts.
These have SC87948R20B on them instead of the MC68881RC20 marking. They
are $75.00 or $80.00 cod and are available on first come first serve
basis.
Vance Chin
{uunet,ucbvax}!unisoft!bdt!bms
or
415 547-2191