The tees are usually part of #CoSoAuction events, or #CoSoMarketplace sales. You can click those tags (& probably have to scroll a lot through ppl mentioning it like this) to see if there are any current offerings for the tees, or maybe find the person who offered them last and @ them [DM or publicly?] to ask about more.
@publickovacs Do it... do it... do it... do it... do it... do it... do it... do it... do it...