Re the Berg Achiever crank pulley: IIRC, that is an all-steel pulley, somewhat heavier than a machined Billet aluminum pulley, with the intent that it acts like an harmonic balancer on the crankshaft. American engines, especially V8s, have been running harmonic balancers for decades, so they know that they work, especially with some of the strange crankshafts that came out of Detroit over the years.
If you already have a balanced engine, 1915cc or less, and you don't expect to spend much time between 5,500-7,000 rpm, then in my opinion an harmonic balancer crank pulley would be a waste of money. For that RPM range, it would be almost as good to run a stock, GERMAN, steel pulley, but then you would lose the degree wheel which can be handy (of course, you could also just mark a stock pulley at 30 degrees BTDC with a file....)
If, otoh, you intend to take it racing and wish to protect the pulley end bearing from distorting the case after, say, 100,000 miles (somewhat farther than you'll probably drive this car) then go ahead and buy an "Achiever" to fit your sand seal.