There is a '66 Pro Reverb for sale locally. My question is, how much should I be willing to pay for this amp if it is in excellent condition? If it has the Jensens, how much more should I be willing to pay than if it has the Oxfords. The issue isn't really the amp itself--I love the blackface Fender sound. But I'm not sure what the market price is right now on these things. I've noticed the amp has received very warm reviews here. Thanks.