MMR does forged rebuilds. The stage 3 rebuild that is good to 600 hp is $1999. That is about the cost of the parts in the list above. It includes labor and an 18 month extended warranty is available.
You can get a new 600 rwhp shortblock for $2699. Extended warranty is also available.
If you like doing it yourself then go for it but I really don't think its cost effective. A second issue is if you need to sell the car. You can tell the buyer it has an MMR short block or you can tell the prospective buyer that you hobby shopped it.