Try Jameson Memorial in Shinrarta Dez...need a permit to get in there to Founder's World.
Couple of hours for 600K? It seems that it's better to not do any regular trading in T6, as trading rares in T6 usually gets you a couple of millions in that time.I'd keep saving and keep an eye on Galnet for a system that's having a sale (or join one of the community events as the rewards are limited time discounts) - although tbh the 10% you'll save it would probably be quicker to run a T6 for a couple of ours to earn that 600K Cr discount in real cash.
The best system to buy and outfit an ASP is CD-51 102
Availability of modules.thank you.
Why this system specifically ?
OP, don't forget to save plenty for some upgrades, insurance and maintenance costs.
I would not touch the Asp before having some 10 million credits plus buy price.
It is much more expensive to run than the T6 or Cobra, and the repair costs can be nasty.