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Maybe not a sweater I would typically wear with this jacket but i am home on break and was pairing things i threw in my bags as I was headed home lol.
This is an appealing, cheerful sweater.
I think your ties are very "business", you need more textured ones, like dupion silk, wool and madder. Your sportcoats and flannel suits would greatly benefit from them
You could try dropping a mail to Patrizio Cappelli. I think he's got madder ties, but they aren't listed on the site, at least not as a separate category. I suspect some ties in the "paisley" and "twill silk" lists are ancient madder, but not 100% sure.
Drakes sells some madders in longer length, those are 9 cm wide and I think a couple of them are very nice.
You could also try Sam Hober, though I don't really like their madder prints for ties (they're too large), but maybe you do