I thought I'd posted it here, but I bought a $20 outward-facing socket from an Ebay dealer, and it works great. It even has a locking tab for the lock in the plug. I just found a link:
http://www.ebay.com/itm/17116865054...iewitem=&sspagename=ADME:L:OC:US:3160&vxp=mtr
http://www.ebay.com/itm/17116865054...iewitem=&sspagename=ADME:L:OC:US:3160&vxp=mtr