Highest Performance HPA BASR build specs?

[hawaiianjuggernaut]

Hi folks, been gone from the game for awhile! Been too busy with my businesses and such.  

Here's my question, what are the highest performance builds in existence for a bolt action HPA system. I want something that'll hit a consistent ~500fps with a 0.2g and will consistently hit at 250ft. 

TM VSR-10 base
Wolverine or Mancraft HPA bolt?  
RHop?  Is that still the go-to top performance, does HSA have something better? 
Hopup chamber? 
Best barrel?

Don't care about pricing on it, just looking for top performance.  Will pay someone to build it if it can nail 300ft consistently with a .43.