Would a glock 23 bbl work in the 27?  Does anyone make an extended G27 bbl?
  yeah, yeah, I already know that you're looking for a few good handgunners...

23 yes, 22 no.

anyone else think a 23 bbl would work in my 27?

The first phase of shortening relocate the lug and caming block in the pistol.  The second phase of shortening allowed the length of the recoil spring system to extend out the front of the slide, thus allowing the spring extra room to use when becoming fully compressed.

Similar change in the 1911, although the first phase of shortening moved the slide's spring tunnel back 1/4 inch, instead of moving the lower lug, link and slidestop pin.  This allowed a 3/4 inch reduction, instead of just cutting 1/2 inch off the front of the slide. The back face of this tunnel is the rearward physical stop.  In the Glock, there is no spring tunnel back face to move, the spring compresses solid to stop rearward travel.  Compressing solid is a bad thing on a 1911, it blows the front off of the spring retaining cap very quickly.

If you want a longer barrel than the standard 23 barrel, contact whoever makes the barrels for FAC and see if you can get one of the threaded or comped barrels before the threads or comp is cut.  Should give you about an extra 1/2"

BTW, Seecamp is a genius.