Cheap transparent wireless<->wired bridges?

The time has come for me to buy some more access points. I'd like them
to work like my current ancient Proxim Harmony ones. The desirable
features for me that these have are:

(a) The access point's IP address, the wired machines' IP addresses, and
the wireless machines' IP addresses can all be in the same class C IP
subnet (and indeed are in my setup)

(b) MAC addresses are preserved over the bridge

(c) Broadcasts make it over the bridge

(d) There can be multiple machines on each side of the bridge

So, for example, the same DHCP server on the wired network segment can
assign DHCP addresses to both wired and wireless clients based on their
MAC. The access point simply passes the traffic, it doesn't run any
servers or do any NAT or whatever itself. (I suspect that our current
ones must maintain ARP tables so that not all unicast traffic everywhere
is repeated on the other segment. Apart from for their own
configuration, I don't think they're IP-aware at all, they probably just
look at MACs.)

I don't mind if I can't get encryption working or if I have to assign
the access points' IP addresses statically. (My current ones get theirs
over DHCP, but that's just a nice-to-have.)

This isn't too much to ask, is it? I'm puzzled because I can't find a
cheap option where it's obvious in advance that it will work. I am happy
to go the route of doing something like buying a Linksys WRT54G and
installing HyperWRT, DD-WRT, OpenWRT, or whatever on it, if that's what
it'll take to keep things cheap. Can anyone confirm that
something-or-other offers something that satisfies the above, that my
existing years-old no-longer-sold access points can already do?

The options I've found so far seem to get upset if you have more than
one machine on both sides of the bridge, or they want to have the
repeated packets sent with the MAC of the bridge, or they get upset if
everything tries to live in the same IP subnet or whatever. I wonder if
one of the third-party WRT firmware options that does proxy ARP might be
good enough? I'd prefer to have some confirmation in advance that it
will work, though, before risking turning an access point into a brick
in reflashing it. (-: (Or, if anyone knows a cheap access point that
will work as an actually-transparent bridge instead of being loaded with
fancy NAT/DHCP/whatever features, that'd be great too. All our NICs are
a/b/g so any type will do.)

-- Mark

I should add that I'm going to have a go with OpenWRT to see if brctl
can bridge wired and wireless.

-- Mark