if you look up tom rapids pro overflow box it goes for around 100-150 online, because it can handle 900 GPH (40-150 gallon tank)
the hose is 8 bucks online. If you wanted the whole thing, which goes for about 250 with the pumps I would do $125. If you just want the overflow box.. $50. nothing structurally wrong with the thing and the overflow is the part that I am more interested in having in the future, but I need a RO/DI unit more. If you notice there is a bulkhead at the bottom of the canister. you could plumb it into your fuge if it was set up right. somebody else will have to pipe in but i thing basically the pump would pull water out of the canister fast enough for them to sit even, but then if you lose power your fuge would siphon into the sump. there would have to be an overflow level for it to work I think. but you could ditch the fuge and use the whole setup no problem. for a small tank like yours you wouldnt need the 700 gph pump I dont think.. I used to power my pvc overflow/bucket sump return with a maxi jet 900. not ideal for flow but this is a surface skimming overflow, so there is that
Edit: some websites are charging close to 400 with the auto fill included.
Edit: http://www.thatpetplace.com/rapids-rp3-pro-plus-filter-system-150-gal?gdftrk=gdfV2226_a_7c268_a_7c6967_a_7c245080&ne_ppc_id=1463&ne_key_id=26542537&gclid=CPCv_siS87UCFQ-xnQodxlYAEg
Edit: seems fair to me considering the cost of the pvc overflow, the look of it, and the fact that this is a real piece of equipment that handles a high flow rate. if anybody thinks that is not a fair price or has any other suggestions feel free to comment because I am not trying to make a sale, I just have something that I think may be a good solution