For crystals you can try Brian at
http://www.af4k.com/crystals.htm
The issued morse key is the J45 with leg clamp. This is a common WW2 item. These often appear on ebay. The H140/U headset uses the 5 pin U229 plug.
The antennas are just a length of wire. Check the manual for length versus frequency and cut your own.
The hardest part to find is the battery case as most dissolved from leaking batteries.