I have the chance to buy this coin in a solid AU for $295. But it has an obvious reverse die clash, does this help or hurt the value of this coin. Do you know whether it is common for this date. And lastly is $295 a good buy
$295 sounds too high for an AU, especially if it's uncertified. For example, a PCGS AU 50 just sold for $253 in the Heritage sale yesterday. Die clashes are not especially uncommon for those coins and don't affect the value, one way or the other. Edited to add: Based on your having asked the questions you did (not that you asked, but) my advise would be to study up a lot more before buying a coin like that.