Went to the Sport Kilt site but the USCG tartan is not up yet. E-mailed them to see what was up and got this reply:

Hi Matt,
We're making the USCG tartan right now, and we expect to have it in our hands by the end of this month, and kilts ready to go in early May, so you may want to check back with us then. Glad to hear the Loch Ness is a hit!!
Best Regards,
Seamus
Sport Kilt

So it's the real deal. (the remark about the Loch Ness Sport Kilt was because I bought one for my son which he really likes)

Matt