I have some Dayton woofers in a band-pass box designed to be a stand for a smaller speaker.

An A/V-1 is setting on one of them just to give you an idea of the size. The one on the right is turned around so you can see the back of it.
It was designed to blend well with a mini-monitor by powering it with an amp and no crossover. The -3db down on the top end is 53.2Hz by the numbers. However the slope was a little too gradual and what it really needed is a sub-woofer plate amp on it to REALLY roll the highs out of it.
See the numbers for it here. The curve for this box is the Green one. The Red on is optimal ported.

And the -3db down on the bottom is 26.7Hz.
This also has 1.5" thick walls.

They need a little cleaning up and some fresh paint wouldn't hurt.
The back panel screws on to service the woofer if needed.
They are slightly heavy. I don't know for sure what they weigh.
Anyway, I'll take
$60 $50 $40 $20 a piece for them plus shipping.
Or, if you order a pair of our SA-1 amps to power them....

See info here on the amp:
http://www.audiocircle.com/index.php?topic=78931.0Then I'll let them go for
FREE plus shipping.
How's that for a deal?