Sounds like your VIsconti experience echos my worst fears. I hadn't considered the porous nature of the material being an issue for absorbing ink but that would also annoy me greatly. Thanks for the feedback.
In terms of overseas suppliers. Ordering from Amazon Japan was no different to Amazon US or UK. I didn't even need a to create a new account. When buying from Amazon I normally ensure the seller is Amazon itself rather than a third party to avoid fakes although apparently this isn't foolproof as Amazon sometimes mixes their own stock with that of third parties (see a recent Pilot Metro post). Cult Pens have been excellent and I've use them several times. They left a Lamy nib out of one order I placed but quickly expedited it to me when I contacted them to report it was missing. Their prices are good and you can get free shipping if you spend enough. I've also used The Pen Company for one order and they were great. I've heard good things about Pensachi but have not personally used them.
Report back about how you like it when it arrives.
You will get a warning notice with this pen because it is ion plated. Sailor will advise to only use their inks in it to avoid plating damage and early reports from ion plated nib owners did suggest that the plating could be damaged, presumably from non-Sailor ink usage. There has been a lot of speculation about why this happened but a general consensus was that acidic inks could be the issue.
Both my Sailors are ion plated and I have chosen not to stick to Sailor only inks but have resiolved to be be selective about what I do put in it. Pilot Iroshizuku inks are generally neutral to slightly alkaline as are the original Herbin line and the DeAtramentis Document line. Waterman inks can be very acidic so stay clear of them despite their great reputation (Serenity Blue has an acidity similar to vinegar). There are a number of websites that have measured the acidity of popular inks you can reference. Also, a number of forum posts on Fountain Pen Network report and discuss the acidity of specific inks.