I've found a very large discrepancy.

These are unsaleable NET fares. I can't even pull up the rules in Galileo. The system inhibits me, perhaps because they can only be bought on the net.

BUE-COR SAT-01JAN05 UNSALEABLE FARES
NET FARES
CX FARE FARE C AP MIN/ SEASONS...... MR GI
ARS BASIS MAX
1 AR 166.00R OAP10 O 10+ 2/14 R WH
2 A7 166.00R NAP10 N 10+ 2/14 R WH
3 A7 208.00R VRT V 4+ 2/15 R WH
4 AR 250.00R LAP21 L 28+ 7/21 R WH
5 A7 250.00R LAP21 L 28+ 7/21 R WH
6 A7 131.00 M M 1+ R WH
7 A7 149.00 K K + R WH
8 A7 169.00 H H + R WH

That first fare is equivalent to US$56 return.

The best, besides the airpasses are some fares of US$66 1-way on AR in B class that are salable only in combination with an international arrival ticket on AR.
USD BASIS
AR 66.00 BVD B
AR 116.00 QVD Q

15. SALES RESTRICTIONS
UNLESS OTHERWISE SPECIFIED
TICKETS MUST BE ISSUED ON/AFTER 01JAN 05.
UNLESS OTHERWISE SPECIFIED
TICKETS MAY NOT BE SOLD IN ARGENTINA.
NOTE -
FARES ONLY APPLY FOR PASSENGER WITH AR
INTERNATIONAL TICKET ARRIVING TO ARGENTINA


There is an agency dealing with youth travel in BA that should have English speakers. Check www.asatej.net. You don't have to be a youth to deal with them; you just can't get youth fares. Perhaps they have a way around this problem. Let us know if you find one.