Modding old frames is fun, do what you like! That said, the forward-facing horizontal dropouts
On old road frames are 10x better than track drops for a street bike.
To answer your questions:
Yes, a good welder can use a mig on this no problem, BUT, you'll have to do a real good job of cleaning out the old brazing material. Maybe use some drop with extra long tabs that will let you cut away a bit of the stays. Henry James sells some for this purpose.
Yes, you can braze it with any oxy/acetylene torch a typical fab shop would have. Any welding supply store will have the brass and flux good enough to do the job.
Finally, I would never tell someone that bending their fork is a good idea....if your dropout mod failed it would be inconvenient, a fork failure could be a whole lot worse!