Hi Chris,
Here is what we use for the connectivity described for every 2 PRI's;
1-NT5D12Ax - Dual port PRI Card
1-NTBK51Ax - D Channel Daughterboard
1-NT5D16DA - Cable 8ft TRK Tip/Ring DDP I/0 ST
2-QCAD133A - TRK Tip/Ring Cable 50ft I/O MDF
As far as resellers go there is a million of them, just Google . But I think I might engage the current Nortel provider for the company or source an authorised Partner @
http://app89.nortelnetworks.com/partnerlocator.asp
Hope this helps!
Rob