Books on piano technique (to compensate for teacher...)

While this quite presumptuous on my part, I'm concerned about any teacher who says "it looks fine" as the point of piano playing is how it sounds.  There are a variety of ways to achieve a particular sound from a technical standpoint.  While I too grant that pain can be a function of building muscles and skill, I don't at all believe that piano playing--particularly if you've been doing it for some time, should be painful.

Without seeing a video of your playing or knowing what score you're trying to learn, it's somewhat difficult to make a recommendation.  Also, technique guides--either written or visual--will only show one perspective or "school" of technique.  For example, the German, French, and Old Russian schools involve entirely different hand postures and wrist positions.  (Horowitz and his famous "flat finger" technique is typical of the Old Russian school, but as a rule, most of us who still play in that fashion focus on having the pads of the fingers strike the keys while not necessarily raising our knuckles as high as he did.)  French and German styles, particularly the German, tend towards a much higher angle of attack with the finger pointed down into the key (thus supported by the bone) for a sharper or harsher sound when the key is pressed.

While any of the schools are going to be generalizations and without more information, I'd recommend looking at your hands and determining what your greatest strengths and weaknesses are physiologically.  From there, you can determine what about your hands you can favor or not as you play, avoiding strange habits of course (one concert pianist got into the terrible habit of 1+3 octaves which is a horribly dangerous idea).  See if there's a way to play that better fits your hand size, shape, and strengths.

'Playing through the pain' is definitely not worth it. The longer you persist, the more you put yourself at risk of not being able to play at all. If you are getting pain when attempting something as basic as a Gr1 arpeggio, there is something fundamentally wrong which needs to be thoroughly investigated. Your teacher should be encouraging and helping you to keep your hand relaxed and flexible so that it doesn't hurt. 'Oh, it looks fine' just doesn't cut it. Time to move on? I would say so, but it's your decision to make.