Is it possible to get the matched receipts on the item level on a vendor bills in a saved search, suiteql or a report? I can't figure out any other way other than going to the vendor bill and looking.

First off, you can link bills to receipts in a search. Here is a mapping on a search result. you can do this either from the sales order or Purchase order. Just make sure Mainline is No.

I have old ones which aren't checked. But my question is on not what should be linked, my question is on what is actually linked.

Do a transaction search on vendor bills and use the applying transaction link type. I think it’s Reciept/Bill. But maybe do a search of all and find the link type that is what you WANT. Then filter to ones that don’t have that link type