Otherwise - I'd probably add a check box for "available on SO/invoice/cash sale" and use that as a saved search filter on my transactions.

Hi, I'm curious as well since this applies to me too. I'm wondering how can a saved search filter the Item list on an invoice/SO/cash sale. If you can give at least an overview, that would be really helpful. Thanks!

Awesome! I kinda hoped though that there is an account filter as well for Journal Entries but there's none.

There is not.