I use CPR aquatics constant siphon O/F boxes, they are awesome and after a year of use its still working just fine.
your sump, what is the holding capacity of it?
I think you will be perfect with a cs102(I got em both, upgraded to the 102 when I set up my 75g, now works friggin awesome) magdrive 9.5 pump and around 10-13g of sump capacity.
THe cpr's are quiet yet require a lift pump that is constantly on, mine makes ZERO noise as its at the bottom of my stairs and my bedroom door is at the top of the stairs and I hear nothing.
Here is my tank, its freshwater but here is the wet/dry with 9.5 MD
Here is the overflow box
Aquacave has em at a decent price.