I just bought some Talbots capris from Poshmark for $15. Hard to tell how slim they are but "stretch" was in the description. They look nicer than strictly casual wear, have cute buttons. Should get them by next week.
Meanwhile, also on Poshmark, I have my eye on another pair by Talbots. Waiting for seller to get back to me on length. If the leg openings are plain and legs are too long, I like these enough to hem them myself. Fingers crossed!
I only buy Talbots and Ralph Lauren pants from Ebay and Poshmark because generally you can't return items. I know that these two brands will fit me perfectly. Same with shoes. Sam Edelman and Keds in my size are always comfortable. Can't say that about other brands.