Depends on your width. I wear a 7.5 in the 2030 and even so need a very thin foam insert for my forefoot. Perfect fit after that. I think a 7 be too small.
I measure an 8E with a high instep, so I'm technically a little wider than that.
In the 5 last, I could get away with a 7.5EE but feel most comfortable with the 7.5EEE.
I wear an 8D in Barrie shoe, 8E in boot; the 7.5E (boot) fits but I can tell itd be uncomfortable after a few hours.
If you're a 7.5D-EE (on the 5 last) with a low instep, I bet a 7 in the 2030 could work. If high instep, err on the other side of larger and use an insert with the 7.5.
That's my best guess.