Combell (Hosting Concepts)
https://www.combell.com/en/
InternetX
https://www.internetx.com/en/
101 Domain.com
https://www.101domain.com/build.htm
United Domains
http://www.uniteddomains.com/new-top-level-domain/build-domain-registration/
Com Laude
http://www.comlaude.com/new-gtlds
Cronon AG / Strato / Deutche Telekom
https://www.strato.de/buy/ger/domain/display/3
GoDaddy Corporate Domains
https://gcd.com/
Synergy Wholesale
https://synergywholesale.com/
Blue Razor
http://www.godaddy.com/tlds/build
one.com
http://www.one.com/en/
RU Center
https://www.nic.ru/en/cgi/na.cgi?step=n_a.ntld&zone=build
Register.com
https://newtlds.register.com/Home/Browse/build
CoreHub
Home...
Gransy
https://regtons.com/en/domains/
Super Registry
http://www.superregistry.co/
Vautron AG
https://www.vautron.de/domain/neue-domain-endungen.php
CSL.de
https://csl.de/
Marcaria
http://www.marcaria.com/register/domain/domain_registration_bulk.asp?country=GTLD-build