AW11 Bottom end failure. Help with choosing/installing replacement engine.

Hey new to the forum, just picked up a ADM facelift AW11 with a bottom end bearing failure.

I'm a 4ag noob. Have replaced an engine in one of my old DR30's before. I'm just wondering other than a sourcing stock standard engine what are my best options and what would need to be changed to get them running right (even the small stuff). I'd like to keep the TVIS at this stage. Willing to swap the manifold over if needed.
 
I'm aiming to do some track day's in it. Whats the general go to option for something performance orientated?
 
Also whats the best way to check the condition of the gearbox before the new engine goes in?
 
Help appreciated!

Hi it was the red one from sunnybank :)
Thanks for the reply, I have considered this option. According to the seller his mechanic said it was due to 'overheating'. Which has me questioning is the head fried as well. I did turn it over and can pretty much be certain that the crank would need work.. Sounded ready to throw a rod.
 
I'm wondering if I grab any import big port engine, can I just bolt the TVIS intake straight on and only be fiddling with a few vac hoses and loom plugs? 

Also while I'm here. I have an 1st gen apexi S-AFC from an ep82 starlet. Is this worth pursuing for better fuel economy and a bit of extra kick on 98 when I get a pod filter sorted and play with timing?

Ok will start looking for an east/west config engine. Thanks.