Found this on ebay. It looks similar to yours. ~$75 shipped.
http://www.ebay.com/itm/200890640551
Here's a 9 Gal version for ~$15 more.
http://www.ebay.com/itm/200890640560
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geeyoupee,
See the link below to see what I did. It's shown in my 5 gallon tun but I've since upgraded to 10 gallon and moved it over. It makes a nice circle in the larger tun. Works great.
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FuBaR1218,
I used a longer braided hose and coiled it on my 5 gallon version. I wrapped some heavy copper wire around a screwdriver and inserted it into the braid to help it keep the coil shape and help prevent it from collapsing.
And for those of you living near a Menards and looking for...