Based on the data provided, we can observe that the coin has had an average auction closing price of 63.04 euros in previous auctions. Additionally, the condition of this coin has been described as '75 (VF).'

Considering that the condition of the coin is 75 (VF) and the average closing price has been 63.04 euros, we can estimate a maximum purchase price around that value or slightly higher, taking into account the trend of previous prices.

Therefore, an estimated maximum purchase price for this coin in the upcoming auction could be around 65-70 euros. It is important to note that this is just an estimate and the final price may vary depending on demand and other factors in the auction.