these are my cranks, they are old Stronglight TSs, but mine have a nice chainguard on it.

but now that i moved my chainring to the back i have a straight chainline. and i would like to keep these if possible cuz i really like the way they look. and also i have been checking out these sealed cartridge BBs. http://www.amazon.com/Orange-Grand-C.../dp/B004JKGQXW
they come in 113 and 107 spindle lengths. you think it would be worth it?