A way to get an existing world (1.7.9) to generate newer fea

Hello all =) So I have this problem just going through my head and was wondering if I could get answers here. I have a 1.7.9 world that I am building a new spawn in for my players. Now I also see that in 1.7.X is going to have underwater temples, and lot of new blocks. I already have been building in the new world for a LONG while now and still am not finished. Me and a couple of other people have built a fair amount already, and we want the new stuff to spawn in the wilderness like it would if we had a new map again. If we do not load any more chunks than the immediate area we are already in, will the world generate the new structures and blocks as players explore later in the future? Or is there a program or a solution to have them spawn naturally as players explore? I really need this, I do not want to have to to painstakingly use World Edit to paste all my builds into another world that will NOT match the land we already have and have the spawn look funky. Thank you for reading and I hope anyone can help.