When I was in college I was on the club cycling team and it was fun, I went to a good share of races, was pretty involved with the team, etc. Now I'm out of college and it's a few years later...is it acceptable for me to wear my old university team kits when I'm out riding casually on my own or with a few friends (not at events)?
I guess it's a matter of opinion, and cyclists have a lot of rules, but personally I would go for it. You were actually on the team after all. I think that the rule #17 from the above link applies here. Personally, I'd rather wear old kit from a team I was personally on than wear kit from a pro team that I have no affiliation with, or even non-pro-kit with logos plastered all over it.
Might even be a great way to start up a conversation with people who recognize the kit, either riders who are currently on the team or even just people who went to that school.