Re: Do you have a picture of a large prague citsuma plant? if you can get taitri, which is hardy in zone 7, use that as a rootstock and you won't have to wait decades. I have a graft on taitri outdoors which has outgrown the original prague I bought from Stan that is on poncirus (2-3 years ago) in just a season.
https://tropicalfruitforum.com..../index.php?topic=546