I have two overflow boxes with stockman mods that can handle 600 gph each with no mod, about 400 gph each with the mod, but a little less flow for complete silence is a pretty good trade off. They appear to be eschopps overflows, and only require 4 1/4" of space behind the tank. They retail new for $60, and before I ship to you I will clean the overflow thoroughly. I would like to get $40 shipped each, or $75 shipped for both. Shipping costs me $10 for each one, so it is really $30 each, $55 for both.
47ea9a4b 2156 cd1f - Overflow boxes
47ea9a4b 2184 eec8 - Overflow boxes
47ea9a4b 21a8 3a6c - Overflow boxes
Without the mod:
47ea9a4b 21c5 0188 - Overflow boxes
47ea9a4b 21df 3200 - Overflow boxes
The mod is removable:
47ea9a4b 2204 d0e0 - Overflow boxes