Perfectly cutting and pasting audio

I would like to update previous hard trance tracks with more modern kick & base. Therefore I would like to mix and record the background to a modern kick & base to my older tracks. I have isolated 2 bars of the kick and base I would like to mix. I need an audio editor to "perfectly" create 2 WAV files - a 32-bar version of the provide file, and also a 34-bar version. The beat grid and timing of the entire track must be perfect.

I will email a WAV file of 32 x 2 beats = 64 beats, plus padding of "just under" one single beat added onto the beginning and end.
A) The small job is to "perfectly" copy the entire 64 beats (2-bars) and create a track of the 32 bars (2 bars repeated 16 times).
The join between each 64-beat/2-bars must be perfect and un-noticable.
Output must remain in a lossless WAV format.
B) Create a WAV file of (A) with a 2-bar padding at the beginning and end. Therefore, the track will be 34-bars.

Thanks for your consideration! Andrew