DWL-810+ (Game adapters) would be an option as well, D-link quit making them because they were being used as Ethernet bridges (rather cheap Ethernet Bridges with removable antennas which could run through an amplifier and have a directional antenna setup to shoot a signal 500 meters up the street.).
D-link doesn't make them anymore because people were using them like I described, when I first started working here they had this chain of D-links all with home brew Power over Ethernet (5 volt voltage regulators and all) and it was highly unreliable for the business it was used for so I switched them over to a Trango bridge and haven't had to touch it since.
one D-link 810 would be fine for what your doing you can probably get one on ebay for cheap cheap. The 820 model has a built in mac address filter, first mac address it see's it allows traffic to pass through, any thing besides that gets dropped. Makes it what it was meant to do, be a 1 unit game adapter.
To be completely honest we still have one DWL-810+ in service bridging 2 buildings in a hotel we have T1 service for...I'm going to have to go find a solution for that (love unused copper wires left over from the phone system.)
But me personally, I would use a WAP and just to it like this:
[Wired Router Lan Port] <---[Straight Cable]---> [WAP Wan Port]
Be sure and turn off DHCP on the WAP and if you do turn on WEP you are cutting your performance in half and it's really not all that good protection anywho, average joe won't beat it but anyone who know's anything about wireless networking can get a sniffer and figure out the private key after a few packets using many available programs. You could also get a wireless router and do do it like this:
[Wired Router Lan Port] <---[Cross Over Cable] ---> [Wireless Router Lan port]
Again turn off DHCP on the wireless router(you will fuck up your network if not) and have the router on a static IP address outside of your DHCP pool. The above basically makes your Wireless Router a WAP and has the benefit of not blocking you from seeing stuff on your wired network where as if you went...
[Wired Router Lan Port] <---[Straight Cable]---> [Wireless Router WAN Port]
You would be on your own network with the router performing NAT and you would not be able to see the other network.
Just some thoughts.