Hello Jim_SharonForrest and welcome to this great forum.
There are a lot of great people here willing to share information.
I'm guessing that you looked everywhere for those two chairs.
Did you point that out to your dealer when you took possession?
Your dealer should be able to help you out.
So if you don't find them and get nowhere with your dealer I suggest that you call Heartland Customer Service.
877-262-8032 / 574-262-8030
Be aware that manufacturers do make changes during production and those chairs may no longer come with a new rig.
I have heard of many people buying their own folding chairs. Seems they may be of better quality.
Peace
Dave