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

1. Current Condition: The coin has a condition rating of 80 (MBC+), indicating that it is in relatively good shape. This suggests that its value should be above that of coins in worse conditions.

2. Auction History:
- The average hammer price for similar coins is 353.08 euros.
- In the past, coins with similar conditions (80) have been auctioned and reached hammer prices of up to 1300 euros (in the case of a condition of 100) and 420 euros (in the case of a condition of 85).
- The last auction of a coin with a condition of 80 had a hammer price of 80 euros.

3. Starting Price and Average Starting Price: The current starting price is 60 euros, which is quite low compared to the average starting price of 243.93 euros.

4. Sales Trends: The coin has been sold in 13 out of the last 14 auctions, indicating good demand.

Based on these factors, an estimated maximum purchase price could be in the range of 300 to 400 euros, considering that the condition is good and that the auction price history for similar coins supports this estimate.

Therefore, a reasonable maximum purchase price could be 350 euros.