I have a Ralph Lauren set that is adorable but might be too hot for this time of year. It's a pair of dark wash jeans, light blue button down shirt(long sleeve) and a sweater vest that is a couple shades of brown/tan/blue...and I do have a couple pairs of 18 month brown dress pants that sorta look like tweed from a distance(ie: not solid) but are lighter weight than that. dress shoes too...
not sure I have much for dressy short sleeved shirts ...ooh, i have a lil clip on red/blue patchwork looking tie that probalby matches a bucket hat I have but my kiddo has a big head so the hat is probalby a 3/4t.
ooh, there were fidoras on clearance at the childrensplace.com yesterday! those with a pair of dress pants, abutton down shirt, shiny shoes and a belt would definitely classify as sunday best
or even with shorts and sneakers! so cute!
i won't be home til 6pm or so but can get pics then if you're interested.
(if you had any specifics in mind that you'd like, let me know, my lil guy has way too many clothes so I might be forgetting about the very thing you are looking for!)
I can mail tomorrow!