I rather not tape the stock pin. Personally, I prefer the reliability of a machined part... but if your on a budget you do what you have to do.
Your statement confuses me.. what you should "get" about the 4b's is that there is no modding required. It is the total package if your going for efficiency.
But as I said before, if your just looking for a replacement bolt critical is the cheapest option.
Never forget... Paintball is a LUXURY sport... calm down.