I have an Apple (brand) IIe Workstation card with the plugin part that mounts on the back with the two mini round connectors. It can be used on to network to other vintage Apple computers, an Apple Laser printer, or be used as a dual serial port. The description, software and manual can be obtained here http://apple2info.net/hardware/a2ews/a2ews.htm
Currently selling on ebay (complete) for $80. I think that offering this for $30 plus shipping is very reasonable. Shipping will be from the USA, and it will come in an antistatic bag. PM me if interested. I would also trade for the Apple IIe Video Overlay Card (with cable connector). If I don't get a response it will go up on ebay after a week or so.