Dave Smith Instruments SYNTHESIZERS

Hi Guys,
My Name is Enrico and I own a MEK. I really love this machine btw.
Anyway, I found some Buchla waveforms yesterday and some of them are longer than the, I think, 126 Samples so the Wave Dump Editor does not accept them.
My question is, is there a tool ready yet, to convert the wav Files into the correct format?
If not, how do I calculate the Time stretching Factor? Unfortunately, I'm not a genius at maths. D;o(

Cheers,