Joined: Jan 2010
Posts: 9,797
Likes: 1,764
From: Northern California
Bikes: Cheltenham-Pedersen racer, Boulder F/S Paris-Roubaix, Varsity racer, '52 Christophe, '62 Continental, '92 Merckx, '75 Limongi, '76 Presto, '72 Gitane SC, '71 Schwinn SS, etc.
Those two small holes either side of the chainring bolts look like crimping or spot welds to me.
I'd guess that it would be hard to remove the small ring without damaging the larger ones that it's attached to.
A grinder might easily take it off, and then you'll need the new chainring and an appropriate set of spacers.
That bolt pattern won't accept anything smaller than 24t, I'm sure of that.