A 50/50 repair cost split in case of unfortunate damage during shipping is not "all risk on the buyer" in my book. I think it's a pretty fair solution to a rare problem (if securely packed).
However, if poorly packed then I'm all in for a 100% refund since the seller deliberately has taken big a risk. I have the same opinion if a parcel get lost when a seller ships without tracking number and not informing the buyer about it.
Gen watches on the other hand is a different thing IMO. Because then you can actually use the shipping insurance if parcel get lost or watch is broken upon arrival, which minimizes the risk for both parties.
Hmm, I don't think there's any way I could fit 1,5mm thick springbars in my 3717 v1 EL's, because the 1,3's were tight enough. Which 3717 version do you have? Maybe the hole size differs between the versions?
I suggest you get both sizes considering the question raised above..
The most effective tool I found carrying out the job in that tiny EL gap is a classic seam ripper from my wife's toolbox.
Normally a EMS parcel should reach you in about a week. But doesn't Canada Post offer some kind of mail forwarding service for a while (for a fee?) when moving to a new location? If they do, sign yourself up and you'll have nothing to worry about.
Me and db2 did an investigation on the 3717 springbars a while back and found the 1.3mm ones being the best match to the rep EL's.. They are quite bitchy getting back on though.. Best of luck!