Quesions concerning Bolivia visa validity

by Eileen
(Ajijic Jalisco Mexico)

I am a US citizen with a 5 year visa that was issued on Sept 2, 2011 and expires on Sept 2, 2016. I would like to visit Bolivia this year (and try to avoid having to pay $160 for a new visa as this will most likely be my last trip). So here are my questions:

If I enter Bolivia less than 30 days before Sept 2, will I be given a stamp that states "Admitido hasta 30 dias" (so I would have 30 days from the date of entry) or "Admitido hasta Sept 2"?

If the latter, could I apply for a visa extension once inside Bolivia to stay beyond Sept 2?