Domus Modern on Etsy has this Knoll Barcelona Chair for sale, and it's a classic yet unique style.
This great chair is for sale at FunkyQuailVintage on Etsy. This color would work with about any space, and would add a touch of the 60s to any room.
This is a clear Lucite chair and table that dates from the 60s, per the information given by brownsugarvintage on Etsy. Aren't they a great set? The only flaw is it wouldn't work too well for hide and seek.