Letter of Recommendation Letterhead Question

Having a past supervisor write my LOR (Letter of Recommendation) for EPIK. HOWEVER....they no longer work at the place we both worked at. Therefore, they don't have access to any official letterhead from that company. The reference never had business cards from the old company, either.

Will they take a letterhead from their new company? A business card from their new company if they have that? What do I do here?