SFF and Low Cost and Low Profile are not compatible. With the current crazy pricing on gpu's with GT1030 being $200 or more there is not anything likely that works for what you want. 1440P requires display port.    
I recently purchased a SFF Dell optiplex 7010 i7 3770 3.4ghz 8core 8GB ram, to use as a new office PC. I was hoping to use my existing 2 screens, one a samsung SMS27A650 @ 1920x1080, the other is a phillips PHL346E2C running at 3440x1440 60hz. My optiplex 980 has a Quadro K620 and runs both at full native resolution, the 7010 won't manage it and reduces both to 1920.  What I would like is something low-cost that can drive the machines at native without sounding like a jet engine or costing vast sums. so, is there a lo-profile quadro or a suitable card that I can run without lots of other faff, like PSU updates. Mostly work applications and videos, not so much gaming will happen, so i'm not looking for 8k 120hz monsters!   Thanks all.
Dell optiplex 7010 i7 3770 3.4ghz 8core 8GB low cost video card upgrade