Fucking ebay. Advice anyone?

The dude only has all positive feedback, but his score is only 42, 8 of which are from being a seller, and the other 34 as a buyer. Not exactly enough leverage to use against him by ruining his feedback score :p.
 
I would have replied "no thanks, I will be leaving you negative feedback, learn how to use ebay idiot."

Seriously, after getting that kind of email I wouldn't even want to fucking deal with him further. He can eat shit. Keep looking man, something will pop up.

Because:

Either:

A: You force him to sell at that price, he gets pissed and breaks your tubes or something (new tubes would be a bastard).
B: He eats shit and actually sells for the price sending you the amp, but leaves you negative feedback just to be a tool.