Lo-tech moon shot

I asked this once before but got no reply, I was wondering if anyone could
help me with this problem before my campaign re-starts.

Problem: 1-5 Individuals of tech 6-8 stranded on an earth type world at TL0,
their only means of returning to civilisation is to get to the TL15 vessel on
the planets moon.

Question: Given time (assuming anagathics if nescessary) could a ship be
built to get to the moon?

One solution offered thus far is a lo-tech Lifting Plane that is got upto
hi altitude by balloons.

I relly _need_ some input to sort this lot out....
Thanks
PAVEWAY