[rescue] SS20 auxiliary video board

[Skeezics Boondoggle]

Sun part# 501-2488.  Would anyone happen to have one of these for sale or
trade?

I've got two 4MB SS20 VSIMMs, and one 8MB SS10 VSIMM.  I suppose I could
trade for a single 8MB SS20 VSIMM, or go pick up a cheap SS10 chassis and
build it up... but I'm thinking that I'd rather have more screen real
estate on one box, since I have a spare Sun 21" monitor gathering dust...  
so I'm trying to track down the board that'd let me drive the 2nd head
using the 2nd 4MB VSIMM at once.  Mmmm, pixels.

How rare are those things?  I've looked around over the last few months,
but not very energetically and without much luck.  Are they pure
unobtainium, or a hardtofindium/unobtainium alloy? :-)

-- Chris