Import Duty on a Gift from a Fellow Collector

A collector in Australia has been very kind and offered to send me some parts to help restore one of my watches back to original condition. I have offered to pay but he is being extremely generous and says he’s happy to help for free. If he goes ahead and posts these parts, does anyone know how important duty would be managed ? I mean, it’s neither my birthday or Christmas Day and I’m not related to the seller in any way. So whilst it is a gift, I can imagine some pretty heavy scepticism from the customs office when I go to pick it up. I am in the EU. Any ideas ? I don’t want to avoid duty if it’s due so the options probably are:

1) ask him to send it as a gift with correct declared value, or
2) ask him to send it as goods with correct declared value (but then I’d have no evidence of paying for it).

I’m in Germany and they’re super efficient and super strict here. If you declare a value they always want to see evidence of payment for it. I don’t mind paying duty, I’d rather that than any stress and interrogation ! It’s hard to guess value, but I’d have thought a couple of hundred euros would be in the right range.

Well I go there a few times every year so they know me, and next week I’ve got to pay duty on just under $2000 so they hopefully realize I’m not a dodger. I’ll talk to the guy in OZ and he can declare gift and a realistic value.

This really might be the most pain free method in the long run.

Values for Germany are as follows:
up to 22 Euros, you don't need to pay anything.
Between 22 and 150 Euros, you have to pay VAT (Mehrwertsteuer).
Above 150 Euros, VAT and import taxes apply.
Attention: Shipping is added to the value of the item!

So if the value is declared below 22 Euros, you are fine.
As @JimInOz said, just ask the sender to write a short letter.
Declaration should indicate used parts or spare parts.