The second Heljan one (PN HEL-653) appears to be larger, but it only services 1 track. That might be the best one for you.
Just for giggles, Bachmann does have another one, but it looks to be a two tracker too. http://www.bachmanntrains.com/home-usa/products.php?act=viewProd&productId=928
My Bachmann Plus coaling tower is the same as the Heljan sand and coaling complex shown. The coaling tower is pretty small. It looks like I'll have to add another track for a larger tower -- they seem to all service two tracks in addition to the dump track.
Walthers has one that might work: http://www.nscalesupply.com/Wal/WAL-933-3823.htm
And Heljan makes two different ones: http://www.nscalesupply.com/HEL/HEL.html Niether of them look like the Bmann one.
I have the small Heljan [Bachmann Plus] coaling tower, which is really pretty small. My yard has a 6-stall roundhouse to service locomotives from 2-8-0's to Challengers. I have water, sand, and diesel facilities as well as the coaling tower. I think I should have a larger coaling tower, but I just have two service tracks -- one to supply the coal, sand, and diesel, and the other for the locomotives on their way to the roundhouse. There is room to add a third track if necessary. Pictures of the Cornerstone concrete tower make it look pretty overwhelming for the rest of my facility. Is there a realistic wooden tower somewhere in between the concrete tower and the one I have?