With up to date firmware they can run up to AIX5.3 but will not support AIX6.
Firmware / microcode updates for the 150:
http://www14.software.ibm.com/webapp...1&mtm=7043-150
Check / google Ebay for prices.
You might get more money for them if you sell them as parts, maybe to an IBM reseller or non-IBM service provider, because some parts can be used in other systems.
Because of the age and not being able to run AIX6 you won't get a lot of money for them.