Dear David,
I tried the MSI at Chicago and no luck. They did have some materials, but no schematic or detailed diagram i.e. blueprints. Only a cross section drawing...(not very detailed) according the their helpdesk. They suggested contacting:

U-Boot Archive
Stiffltung Traditions Archiv Unter See Boote
27478 Cuthaven-Altenbruch
Germany (Phone: 011-49-22-3-22)

Finding plans for a Type VII seems to be somewhat difficult, but I have received emails from a couple of firms that can reproduce the plan. One such firm is:

Taubman Plans Service
11 College Drive, Box 4G
Jersey City, NJ 07305
Ph: (201)435-5205
FAX201)985-0438

I hope this helps someone. I plan to contact them myself and acquire at least one set for future modeling endeavours.
Clark