Tbh I think diplo clans are dying/dead as the crossover (diplo+strat) clans are leaning toward strat these days. Your boot rate is also concerning.https://www.warlight.net/Clans/?ID=163
USSR is probably the biggest pure-diplo clan. Don't know about activity.
Other than that, you seem to have played a bunch of multi-day diplos. Maybe you can find some players from those and check their clan tags, then ask for an invite.
CORP isn't all that diplo these days but they/we are active so you might be able to get something out of that. I don't know if they'll take you with a high boot rate.