I haven't ordered anything from Germany since I had the following experience back in the summer of this year: https://www.cointalk.com/threads/i-think-this-wait-is-unreasonable.366695/#post-4862528. Perhaps things have improved since then, but I'm not willing to take the risk of such a lengthy delay right now.
Looks to be quite similar to my own experience. Even though a couple parcels have shipped smoother, I too have been a little apprehensive of ordering anything from Germany. My long delay was this last time around. I had even gone as far as starting the process of filing a protection claim with my payment issuer, and suggesting to the auction house to start the indemnity claim process with their insurer on their own end. After 3+ months(2+ with no tracking updates), I was sure it had to be lost in transit. Fortunately for the OP's sake, their parcel is coming from Switzerland, for which I've personally had no recent problems for reasonably timely delivery.
My experience has been that sometimes it's a few days, and at times it's been an average of a week or two to process through customs and the NY ISC. Once in USPS possession, and when tracking starts regularly updating again; it has been fairly standard delivery time based on zoning. As long as the last tracking info reads: "Forwarding to country of destination" (or something of the sort), that usually means that it has made it to the U.S. It is waiting to be processed through customs, before being sorted and then handed off to the postal service. For parcels that have been routed the other direction, the S.F. ISC seems to have been a little more efficient, FWIW. Good luck.
I also live in Canada/ Orleans. I have just great experiences with Swiss post. Coins always arrived in 1-2weeks. Best thing, they send coins discreetly not to get dinged by customs
I know I'm a little late to the thread, but it does the same for me when coming to Australia. Usually they're here in 3 weeks or less, more like 5-6 during covid. One thing you can do is call Canada Post after a couple weeks if it hasn't arrived, they'll have their own internal tracking which should show where your package is even if the online tracking doesn't have it as 'trackable'. That's what I do with AusPost since registered international mail doesn't have website tracking but does have internal tracking with the postal carrier. Also I 100% agree with @panzerman on using registered mail, even moreso for valuable coins. I've never had anything lost (fingers crossed) and never had to pay customs either.