Small Footprint SS Power Amps

If you can afford and have the room
THOSE VINCENT monoblocs are simply wicked great. 
Vincent T-700 monos. Amazing German amps!
if I had the coin, I would be all over them!

 Dropping 800 on the avantone cl-200 in another week for a backup amp.

 Will be watching  my saved stash for enough for those Vincent monos.

Monarchy Audio.

i think that lil mighty mite parasound zamp can be strapped mono - gets about 100 wpc iirc

“14" or less wide.”

The dimension limitations regarding depth and height would be of use in providing you, The Original Poster, accurate recommendations. 

Adcom GFA-1A, Belles II, Carver The Cube, Quad 303 and 405, SWTP 207. All narrower designs. I have them in my amp collection.