Knocking => rebuild.Parts suggestions?

[azerty]

Hi all.
My Supra has developed a knock, that starts from 2000 rpm. It is louder when at WOT.
From this my mechanic said it must be something about the crankshaft and the bearings in that area.
Could this be it?
If so, I am looking at a rebuild, am I not?
So, if a take the engine apart, I as well change some other stuff around there, right?
I have to mention that I am building this Supra for the races, so I am looking in the future for a big increase in power.
Considering al that, what would you recommend I shold change..
Please be as specific as you can when refering to a new part, as if talking about the HG, don't say "change the HG with a MHG", but indicate "buy a HKS MHG this type", or "buy ARP studs, not ARP bolts"
Thanks in advance.
I look forward to your input.
PS. Is there a aftermarket crankshaft capable of holding more than stock HP?
How much will the stick one hold?