PornBox.com

Are there any milk in ass content out here?

Sure - loads. For a time it was probably the main kink on this site, with scenes like this dropping every few days: https://pornbox.com/application/watch-page/27799
Unfortunately in recent years it's become much rarer. but it still happens occasionally.

Do you have any more recent?

Here's one: https://pornbox.com/application/videos

Sorry, that didn't come out right. Giorgio has a couple of scenes labelled 'milk overflow', like this https://pornbox.com/application/watch-page/217094
I think the glory days stuff was labelled mostly as 'kreme' https://pornbox.com/application/search/kreme but finding this stuff is difficult, as there doesn't seem to be a constitent tag. I've definately seen the occasional milk enema style action scene recently, but tracking them down now through thousands of scenes is proving difficult.,,