To estimate a maximum purchase price for the coin in question, we will consider several factors:

1. Current Condition: The coin has a condition rating of 75 (MBC), indicating that it is in fairly good shape, but not of the highest quality (FDC).

2. Auction History:
- The average hammer price for similar coins in the past has been 278.38 euros.
- The coin has been auctioned 59 times, of which it has sold 56 times, indicating good demand.
- Previous hammer prices for coins with similar conditions (70-80) have varied, but generally, they have been in a range of 220 to 400 euros, depending on the condition and demand at the time of the auction.

3. Starting Price and Estimates:
- The current starting price is 300 euros, which is slightly higher than the average starting price of 221.23 euros.
- The estimated price for this auction is 300 euros, suggesting that the seller has expectations of a good sale.

4. Recent Trends: In the most recent auctions, hammer prices have been in the range of 320 to 500 euros for coins of similar condition, especially in favorable market conditions.

Based on these factors, an estimated maximum purchase price for this coin could be in the range of 350 to 400 euros. This range takes into account the good condition of the coin, historical demand, and the current starting price. However, it is important to note that the final price may vary depending on competition in the auction and the interest of other buyers.