Could be Roger is tired of dealing customers in the USA?
Last time I ordered from RGM/Roger, it was all done on the website. Orders showed up promptly. Probably 3 years ago maybe more. Initially before my first order email was responded to. Email has not been responded to since. (I may not have had the email address with the secret handshake.) I don't bother with email. I hope Roger's website doesn't get turned into a poor excuse of a searchable text only database. Running a website that looks like it was created in the late 1980's is not very impressive.
You might have to order most of the pieces separately for the belt clutch. Pre-Commando alternator kits are not in stock. Which might be why you get no answers to email related to the Atlas belt drive. I have the 30mm belt that used to come with those pre-Commando kits if you want it.
I did see Bonzo's note from Roger about the website issues. Try doing it like Roger suggests.
Edit: If your customer has a lot of money to burn you could try TGA and Andy Molnar. He has NEB belt clutches.