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

1. Current Condition: The coin has a condition of 70 (MS-). This is an important factor, as coins in better condition tend to reach higher prices.

2. Previous Prices: By observing previous auction prices for coins with similar conditions, we can see that:
- Coins with a condition of 70 have reached auction prices of up to 340 euros.
- Coins with a condition of 80 have reached auction prices of up to 460 euros.
- Coins with a condition of 85 have reached auction prices of up to 600 euros.

3. Starting Price and Average Hammer Price: The current starting price is 325 euros, and the average hammer price in the past has been approximately 287.76 euros. This suggests that the starting price is relatively high compared to the average hammer price.

4. Recent Trends: In the most recent auctions, hammer prices have been higher, especially for coins with conditions above 70. This could indicate an upward trend in interest for coins of this reference.

5. Estimation Based on Previous Prices: Given that the coin has a condition of 70, a hammer price in the range of 300 to 350 euros seems reasonable, considering that there have been previous auctions in this range for similar conditions.

Based on these factors, an estimated maximum purchase price for this coin could be between 350 and 400 euros. This takes into account the possibility that bidders may be willing to pay a little more due to demand and the condition of the coin.