Does the Foundation ever consider sending the devices themselves from the EU, e.g. to Austria, Switzerland, etc.? Then you don't have to trust the reseller.
They ship international to most countries but shipping can be expensive, so I recently saw someone who is opening EU based shop, but I am not sure if this is official reseller or not.
Maybe you should contact Foundation team to find more information about this.
But you can not deliver the package to the parcel lockers. Because of customs etc. there are problems. For example, Keystone has recently started to deliver directly from Europe.
Is this Keystone Amazon EU store opened or you are talking about something else?