O.S. for IBM RT 6151 model 115

[Francois Normant]

I have an IBM RT 6151 model 115 (advanced Processor Card with 4 MB of fast 
memory (sic), 70 MB Extended ESDI Fixed-Disk Drive) + etherned card and
floating point accelerator.

I'm trying to reinstall (from scratch) an operating system.

1) Is AOS4.3 still available, from where, for how much ?

2) Does AIX 2.2.1 fit on a 70 MB disk ? 

3) Considering that I want to use this RT only for e-mail and remote login on
other hosts (not computation nor programmming), if I have the choice between AOS
and AIX, which one should I chose ?

Any advice would be welcome.

Thanks
-- 
Francois Normant - fn at math.yale.edu
Yale University - Mathematics Department
Box 2155 - Yale Station
New Haven CT 06520