Bill,

Try M48TO2-150PC1, instead of M48TO2-200PC1.

The difference is just 150 ns access memory speed versus 200 ns.  The 200 ns part is going obsolete.  There is also a 70 ns part with number M48TO2-70PC1.  All are OK, because the memory just has to be "fast enough" to support the system it is in, namely the VM1000.

Tom Thibault