Most of the well water systems on the east coast will have a plastic line from the well into the house. Although I’ve not heard or seen PB used, it is no more apt to leak than any other plastic. At worst your line has two fittings, one you can get to at the presure tank (and bad fittings [acetal?] was one of the largest causes of leaks with PB tubing) and you have had no chlorine in the water. Plus it hasn’t leaked so far in 8 years. Also, your fitting at the well should be brass because it is underground.
If I were you, I’d tell anyone wanting to buy the house what I’ve said, ask them to prove it/me/you wrong and that I am not replacing it. Period. You can also tell them that most leaks were on much higher pressure systems than your well system and that if it leaks they can run a new line rather than digging up the old one and replacing it which would be much cheaper and wouldn’t distrub the electrical cable.
And if eventually you have to give in… rather than replacing or putting in a new line, I’d get a good idea (now) of what the cost to run a new line would be and reduce the sales price by half of that amount and only go to the whole amount if I were forced to. That would only be to someone having already signed a sales agreement, as you may have now to be going through an inspection.
You realize the inspector is doing some CYA stuff here right?
Quality Water Associates