Ya, that sump design sounds fine, although my experience with filter socks is they are pretty high maintenance. There are flow rate calculators for weir/overflow drain size/etc, 1" 'should' be ok, but I'd double-check.
I completely sympathize with fitting the sump inside the stand...but I was easily able to fit a 50G under my 125G tank... Go get a cheap used 50 or something at least...doesn't need to be pretty, just needs to hold water. It's the volume you need.
Dunno, maybe I'm way off, but I'd do my darndest to get something bigger.