Ähem... Steel Beasts your liking...?
It should run with your CPU, I ran it on a Pentium 4 3 GHz, that was single core. The video RAM on your gfx however - I cannot say.
Be advised that the new version released in summer or later this year will come with a
new graphics engine which probably will be more demanding on the hardware, so there is a chance that while you an get the old engine now and be able to run it, this window will be closed for you once the new version is out (the old versions will probably not be sold anymore then).
If you want to get the old version for your older hardware, your time is slowly running out.
Internet is no problem, you need to get the dongle via mail, and somebody can send you the software on CD if downloading it works too slow for you. Has been done before like that, you're not the first.
You can test it - whether it runs on your rig - via a guest license. Ask in the eSim forum for one.
On tanks, there is just one sim out there.